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authorRoland McGrath <roland@hack.frob.com>2015-04-17 09:02:19 -0700
committerRoland McGrath <roland@hack.frob.com>2015-04-17 09:02:19 -0700
commitd1e44df1fa5fefd8a083f6c1e909bbcdc97c6438 (patch)
treea76176eca62c0907dd7f135979312c8e55ad06a5
parentf70925993ada98039250d46c62fb89c168b8f9d6 (diff)
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Add arm-nacl port.
-rw-r--r--ChangeLog7
-rw-r--r--abi-tags2
-rw-r--r--sysdeps/arm/nacl/Implies2
-rw-r--r--sysdeps/arm/nacl/Makefile33
-rw-r--r--sysdeps/arm/nacl/____longjmp_chk.S47
-rw-r--r--sysdeps/arm/nacl/aeabi_read_tp.S44
-rw-r--r--sysdeps/arm/nacl/arm-features.h43
-rw-r--r--sysdeps/arm/nacl/dl-machine.h53
-rw-r--r--sysdeps/arm/nacl/dl-trampoline.S278
-rw-r--r--sysdeps/arm/nacl/include/bits/setjmp.h38
-rw-r--r--sysdeps/arm/nacl/shlib-versions4
-rw-r--r--sysdeps/arm/nacl/start.c1
-rw-r--r--sysdeps/arm/nacl/sysdep.h69
-rw-r--r--sysdeps/arm/nacl/tls.h2
-rw-r--r--sysdeps/nacl/Implies3
-rw-r--r--sysdeps/nacl/Makefile135
-rw-r--r--sysdeps/nacl/Subdirs3
-rw-r--r--sysdeps/nacl/Versions21
-rw-r--r--sysdeps/nacl/_exit.c34
-rw-r--r--sysdeps/nacl/access.c28
-rw-r--r--sysdeps/nacl/backtrace.c1
-rw-r--r--sysdeps/nacl/bits/dirent.h52
-rw-r--r--sysdeps/nacl/bits/fcntl.h149
-rw-r--r--sysdeps/nacl/bits/local_lim.h64
-rw-r--r--sysdeps/nacl/bits/mman.h24
-rw-r--r--sysdeps/nacl/bits/param.h23
-rw-r--r--sysdeps/nacl/bits/posix_opt.h210
-rw-r--r--sysdeps/nacl/bits/stat.h147
-rw-r--r--sysdeps/nacl/bits/typesizes.h71
-rw-r--r--sysdeps/nacl/brk.c93
-rw-r--r--sysdeps/nacl/chdir.c28
-rw-r--r--sysdeps/nacl/check_fds.c23
-rw-r--r--sysdeps/nacl/chmod.c28
-rw-r--r--sysdeps/nacl/clock.c29
-rw-r--r--sysdeps/nacl/clock_getres.c28
-rw-r--r--sysdeps/nacl/clock_gettime.c29
-rw-r--r--sysdeps/nacl/close.c31
-rw-r--r--sysdeps/nacl/configure18
-rw-r--r--sysdeps/nacl/configure.ac18
-rw-r--r--sysdeps/nacl/createthread.c46
-rw-r--r--sysdeps/nacl/dl-map-segments.h238
-rw-r--r--sysdeps/nacl/dl-osinfo.h34
-rw-r--r--sysdeps/nacl/dl-sysdep.c89
-rw-r--r--sysdeps/nacl/dl-sysdep.h30
-rw-r--r--sysdeps/nacl/dl-unmap-segments.h65
-rw-r--r--sysdeps/nacl/dl-writev.h45
-rw-r--r--sysdeps/nacl/dup.c30
-rw-r--r--sysdeps/nacl/dup2.c31
-rw-r--r--sysdeps/nacl/entry.h6
-rw-r--r--sysdeps/nacl/errnos.awk87
-rw-r--r--sysdeps/nacl/euidaccess.c27
-rw-r--r--sysdeps/nacl/exit-thread.h35
-rw-r--r--sysdeps/nacl/fchdir.c28
-rw-r--r--sysdeps/nacl/fchmod.c28
-rw-r--r--sysdeps/nacl/fdatasync.c28
-rw-r--r--sysdeps/nacl/fork.c3
-rw-r--r--sysdeps/nacl/fsync.c27
-rw-r--r--sysdeps/nacl/ftruncate.c32
-rw-r--r--sysdeps/nacl/ftruncate64.c1
-rw-r--r--sysdeps/nacl/fxstat.c45
-rw-r--r--sysdeps/nacl/fxstat64.c1
-rw-r--r--sysdeps/nacl/getcwd.c56
-rw-r--r--sysdeps/nacl/getdents.c29
-rw-r--r--sysdeps/nacl/getdents64.c1
-rw-r--r--sysdeps/nacl/getdtsz.c28
-rw-r--r--sysdeps/nacl/getpagesize.c1
-rw-r--r--sysdeps/nacl/getpid.c32
-rw-r--r--sysdeps/nacl/getsysstats.c65
-rw-r--r--sysdeps/nacl/gettimeofday.c40
-rw-r--r--sysdeps/nacl/glob.c26
-rw-r--r--sysdeps/nacl/glob64.c1
-rw-r--r--sysdeps/nacl/ifaddrs.c2
-rw-r--r--sysdeps/nacl/init-first.c27
-rw-r--r--sysdeps/nacl/iofdopen.c26
-rw-r--r--sysdeps/nacl/irt.sed12
-rw-r--r--sysdeps/nacl/isatty.c38
-rw-r--r--sysdeps/nacl/kernel-features.h28
-rw-r--r--sysdeps/nacl/ldsodefs.h35
-rw-r--r--sysdeps/nacl/libc-start.c4
-rw-r--r--sysdeps/nacl/link.c28
-rw-r--r--sysdeps/nacl/lowlevellock-futex.h87
-rw-r--r--sysdeps/nacl/lseek.c43
-rw-r--r--sysdeps/nacl/lseek64.c1
-rw-r--r--sysdeps/nacl/lxstat.c46
-rw-r--r--sysdeps/nacl/lxstat64.c1
-rw-r--r--sysdeps/nacl/mkdir.c28
-rw-r--r--sysdeps/nacl/mmap.c49
-rw-r--r--sysdeps/nacl/mmap64.c1
-rw-r--r--sysdeps/nacl/mprotect.c33
-rw-r--r--sysdeps/nacl/munmap.c32
-rwxr-xr-xsysdeps/nacl/nacl-after-link.sh69
-rw-r--r--sysdeps/nacl/nacl-interface-list.h47
-rw-r--r--sysdeps/nacl/nacl-interface-table.c43
-rw-r--r--sysdeps/nacl/nacl-interfaces.c123
-rw-r--r--sysdeps/nacl/nacl-interfaces.h108
-rw-r--r--sysdeps/nacl/nacl-interfaces.mk.in25
-rwxr-xr-xsysdeps/nacl/nacl-test-wrapper.sh280
-rw-r--r--sysdeps/nacl/nacl_interface_query.c49
-rw-r--r--sysdeps/nacl/nanosleep.c33
-rw-r--r--sysdeps/nacl/open.c52
-rw-r--r--sysdeps/nacl/open64.c1
-rw-r--r--sysdeps/nacl/preconfigure7
-rw-r--r--sysdeps/nacl/profil.c2
-rw-r--r--sysdeps/nacl/read.c32
-rw-r--r--sysdeps/nacl/readdir.c11
-rw-r--r--sysdeps/nacl/readdir64.c1
-rw-r--r--sysdeps/nacl/readdir64_r.c1
-rw-r--r--sysdeps/nacl/readdir_r.c8
-rw-r--r--sysdeps/nacl/readlink.c32
-rw-r--r--sysdeps/nacl/rename.c27
-rw-r--r--sysdeps/nacl/rmdir.c28
-rw-r--r--sysdeps/nacl/sched_yield.c31
-rw-r--r--sysdeps/nacl/shlib-versions9
-rw-r--r--sysdeps/nacl/sigaction.c11
-rw-r--r--sysdeps/nacl/sprofil.c2
-rw-r--r--sysdeps/nacl/start.c73
-rw-r--r--sysdeps/nacl/symlink.c28
-rw-r--r--sysdeps/nacl/tls.h41
-rw-r--r--sysdeps/nacl/truncate.c32
-rw-r--r--sysdeps/nacl/truncate64.c1
-rw-r--r--sysdeps/nacl/unlink.c28
-rw-r--r--sysdeps/nacl/utimes.c29
-rw-r--r--sysdeps/nacl/write.c33
-rw-r--r--sysdeps/nacl/xstat.c45
-rw-r--r--sysdeps/nacl/xstat64.c1
-rw-r--r--sysdeps/nacl/xstatconv.c76
-rw-r--r--sysdeps/nacl/xstatconv.h32
127 files changed, 5120 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index 215fd119a2..44dc704b55 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-04-17  Roland McGrath  <roland@hack.frob.com>
+
+	Add preliminary port to Google Native Client on ARM.
+	* abi-tags (.*-.*-nacl.*): New entry.
+	* sysdeps/arm/nacl: New directory.
+	* sysdeps/nacl: New directory.
+
 2015-04-16  David S. Miller  <davem@davemloft.net>
 
 	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h: Make use of
diff --git a/abi-tags b/abi-tags
index 87cd6816a9..150d29b991 100644
--- a/abi-tags
+++ b/abi-tags
@@ -28,5 +28,7 @@
 
 .*-.*-syllable.*	5	2.0.0	# just an arbitrary value
 
+.*-.*-nacl.*		6	42.0.0	# earliest compatible Chromium version
+
 # There is no catch-all default here because every supported OS that uses
 # ELF must have its own unique ABI tag.
diff --git a/sysdeps/arm/nacl/Implies b/sysdeps/arm/nacl/Implies
new file mode 100644
index 0000000000..2294208dba
--- /dev/null
+++ b/sysdeps/arm/nacl/Implies
@@ -0,0 +1,2 @@
+arm/nptl
+init_array
diff --git a/sysdeps/arm/nacl/Makefile b/sysdeps/arm/nacl/Makefile
new file mode 100644
index 0000000000..c9226595e6
--- /dev/null
+++ b/sysdeps/arm/nacl/Makefile
@@ -0,0 +1,33 @@
+# Makefile fragment for ARM/NaCl configurations.
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+# sysdeps/nacl/Makefile needs this set to the architecture suffix used in
+# the NaCl SDK.
+nacl-sdk-arch = arm
+
+# We don't really support TLSDESC, even though the compiler thinks it does.
+have-arm-tls-desc = no
+
+ifeq ($(subdir),csu)
+sysdep_routines += aeabi_read_tp
+endif
+
+ifeq ($(subdir),elf)
+sysdep-rtld-routines += aeabi_read_tp
+endif
diff --git a/sysdeps/arm/nacl/____longjmp_chk.S b/sysdeps/arm/nacl/____longjmp_chk.S
new file mode 100644
index 0000000000..f950f17d7b
--- /dev/null
+++ b/sysdeps/arm/nacl/____longjmp_chk.S
@@ -0,0 +1,47 @@
+/* longjmp that validates stack addresses.  ARM/NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+	.section .rodata.str1.1,"aMS",%progbits,1
+	.type	longjmp_msg,%object
+longjmp_msg:
+	.string "longjmp causes uninitialized stack frame"
+	.size	longjmp_msg, .-longjmp_msg
+
+	.text
+
+/* We don't have sigaltstack and so any longjmp must be to an outer frame.  */
+.macro check_sp reg
+	cmp sp, \reg
+	bls .Lok
+#ifdef PIC
+	movw r0, #:lower16:longjmp_msg-(.LPIC0+8)
+	movt r0, #:upper16:longjmp_msg-(.LPIC0+8)
+.LPIC0:	add r0, r0, pc
+#else
+	movw r0, #:lower16:longjmp_msg
+	movt r0, #:upper16:longjmp_msg
+#endif
+	b HIDDEN_JUMPTARGET(__fortify_fail)
+.Lok:
+.endm
+
+#define CHECK_SP(reg)	check_sp reg
+#define __longjmp	____longjmp_chk
+#include <__longjmp.S>
diff --git a/sysdeps/arm/nacl/aeabi_read_tp.S b/sysdeps/arm/nacl/aeabi_read_tp.S
new file mode 100644
index 0000000000..153e6dbdcb
--- /dev/null
+++ b/sysdeps/arm/nacl/aeabi_read_tp.S
@@ -0,0 +1,44 @@
+/* ARM EABI helper function for reading the thread pointer.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file with other
+   programs, and to distribute those programs without any restriction
+   coming from the use of this file. (The GNU Lesser General Public
+   License restrictions do apply in other respects; for example, they
+   cover modification of the file, and distribution when not linked
+   into another program.)
+
+   Note that people who make modified versions of this file are not
+   obligated to grant this special exception for their modified
+   versions; it is their choice whether to do so. The GNU Lesser
+   General Public License gives permission to release a modified
+   version without this exception; this exception also makes it
+   possible to release a modified version which carries forward this
+   exception.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+/* GCC will emit calls to this routine under -mtp=soft.  */
+
+	.hidden __aeabi_read_tp
+ENTRY (__aeabi_read_tp)
+	ldr	r0, [r9]
+	sfi_bx	lr
+END (__aeabi_read_tp)
diff --git a/sysdeps/arm/nacl/arm-features.h b/sysdeps/arm/nacl/arm-features.h
new file mode 100644
index 0000000000..b00cfdbfa5
--- /dev/null
+++ b/sysdeps/arm/nacl/arm-features.h
@@ -0,0 +1,43 @@
+/* Macros to test for CPU features on ARM.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _NACL_ARM_FEATURES_H
+#define _NACL_ARM_FEATURES_H 1
+
+#ifdef __SOFTFP__
+# error NaCl should always have VFP enabled
+#endif
+
+/* NaCl does not support iWMMXt at all.  */
+#define ARM_ASSUME_NO_IWMMXT    1
+
+/* NaCl does not allow instructions to target the pc register.  */
+#define ARM_ALWAYS_BX           1
+
+/* Computed branch targets must be bundle-aligned, which is to 16 bytes.  */
+#define ARM_BX_ALIGN_LOG2       4
+
+/* Two-register addressing modes are never allowed.  */
+#define ARM_NO_INDEX_REGISTER   1
+
+/* Only ARM mode code is allowed, never Thumb mode.  */
+#define NO_THUMB
+
+#include_next <arm-features.h>
+
+#endif  /* arm-features.h */
diff --git a/sysdeps/arm/nacl/dl-machine.h b/sysdeps/arm/nacl/dl-machine.h
new file mode 100644
index 0000000000..81f3755b3b
--- /dev/null
+++ b/sysdeps/arm/nacl/dl-machine.h
@@ -0,0 +1,53 @@
+/* Machine-dependent ELF dynamic relocation inline functions.  ARM/NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef dl_machine_h
+
+/* This is only needed for handling TEXTRELs and NaCl will never
+   support TEXTRELs at all.  */
+#define CLEAR_CACHE(start, end) __builtin_trap ()
+
+#endif
+
+/* The rest is just machine-specific.
+   This #include is outside the #ifndef because the parts of
+   dl-machine.h used only by dynamic-link.h are outside the guard.  */
+#include <sysdeps/arm/dl-machine.h>
+
+#ifdef dl_machine_h
+
+/* Initial entry point code for the dynamic linker.
+   The C function `_dl_start' is the real entry point;
+   its return value is the user program's entry point.  */
+#undef RTLD_START
+#define RTLD_START asm ("\
+.text\n\
+.globl _start\n\
+.type _start, %function\n\
+.p2align 4\n\
+_start:\n\
+	@ r0 has the pointer to the info block (see nacl_startup.h)\n\
+	mov r1, sp              @ Save stack base for __libc_stack_end.\n\
+	push {r0-r3}            @ Push those, maintaining alignment to 16.\n\
+	mov r0, sp              @ Pointer to {info, sp} is argument.\n\
+	sfi_bl _dl_start\n\
+	pop {r1-r4}             @ Restore stack, getting info block into r1.\n\
+	mov lr, #0              @ Return address for noreturn call.\n\
+	b _dl_start_user");
+
+#endif
diff --git a/sysdeps/arm/nacl/dl-trampoline.S b/sysdeps/arm/nacl/dl-trampoline.S
new file mode 100644
index 0000000000..47bc0cac79
--- /dev/null
+++ b/sysdeps/arm/nacl/dl-trampoline.S
@@ -0,0 +1,278 @@
+/* PLT trampolines.  ARM/NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+	.syntax unified
+	.text
+
+@ Change &GOT[n+3] into 8*n.  Note relocs are 8 bytes each.
+.macro compute_reloc_arg pltgot, got2
+	sub r1, \pltgot, \got2	@ r1 = &GOT[n+3] - &GOT[2] = 4*(n-1)
+	sub r1, r1, #4		@ r1 = 4*n
+	add r1, r1, r1		@ r1 *= 2 = 8*n
+.endm
+
+	CFI_SECTIONS
+	.globl _dl_runtime_resolve
+	.type _dl_runtime_resolve, %function
+	.p2align 4
+_dl_runtime_resolve:
+	cfi_startproc
+	cfi_adjust_cfa_offset (8)
+
+	@ We get called with:
+	@ 	lr contains the return address from this call
+	@	stack[1] contains &GOT[n+3] (pointer to function)
+	@	stack[0] points to &GOT[2]
+
+	ldr ip, [sp]		@ ip gets &GOT[2]
+
+	@ Save the argument registers and the return address.
+	@ r4 doesn't need to be saved, but it makes the total
+	@ adjustment to sp (including the two words pushed by
+	@ the PLT code) an even eight words, so sp stays aligned.
+	push {r0-r4, lr}
+	cfi_adjust_cfa_offset (24)
+	cfi_rel_offset (r0, 0)
+	cfi_rel_offset (r1, 4)
+	cfi_rel_offset (r2, 8)
+	cfi_rel_offset (r3, 12)
+	cfi_rel_offset (r4, 16)
+	cfi_rel_offset (lr, 20)
+
+	ldr r1, [sp, #28]	@ r1 gets &GOT[n+3]
+
+	@ Get the 'struct link_map *' for the first argument to _dl_fixup.
+	sfi_breg ip, ldr r0, [\B, #-4]
+
+	@ Get the reloc offset for the second argument to _dl_fixup.
+	compute_reloc_arg r1, ip
+
+	@ This does the real work, and returns the real call target.
+	sfi_bl _dl_fixup
+	mov ip, r0
+
+	@ Restore the saved registers.
+	pop {r0-r4, lr}
+	cfi_adjust_cfa_offset (-24)
+	cfi_restore (r0)
+	cfi_restore (r1)
+	cfi_restore (r2)
+	cfi_restore (r3)
+	cfi_restore (r4)
+	cfi_restore (lr)
+
+	@ Now compensate for the two words pushed by the PLT code.
+	sfi_sp add sp, #8
+	cfi_adjust_cfa_offset (-8)
+
+	@ Finally, jump to the newfound call target.
+	sfi_bx ip
+
+	cfi_endproc
+	.size _dl_runtime_resolve, .-_dl_runtime_resolve
+
+#ifndef PROF
+	.globl _dl_runtime_profile
+	.type _dl_runtime_profile, #function
+	.p2align 4
+_dl_runtime_profile:
+	cfi_startproc
+	cfi_adjust_cfa_offset (8)
+
+	@ We get called with:
+	@ 	lr contains the return address from this call
+	@	stack[1] contains &GOT[n+3] (pointer to function)
+	@	stack[0] points to &GOT[2]
+
+	@ Stack layout:
+	@ sp + 204		framesize returned from pltenter
+	@ sp + 12		La_arm_regs
+	@ sp + 4		Saved two arguments to _dl_profile_fixup
+	@ sp + 0		outgoing argument to _dl_profile_fixup
+	@ For now, we only save the general purpose registers.
+# define PLTEXIT_ARGS		4
+# define LA_ARM_REGS		(PLTEXIT_ARGS + 8)
+# define LA_ARM_REGS_SIZE	(4 * (4 + 1 + 1 + 42))
+# define PLTENTER_FRAMESIZE	(LA_ARM_REGS + LA_ARM_REGS_SIZE)
+# define FRAMESIZE		(((PLTENTER_FRAMESIZE + 4) + 15) & -16)
+
+	@ The NaCl ABI requires that sp be aligned to 16 bytes at call
+	@ sites.  Assuming that was met on entry to the PLT, sp is
+	@ now exactly 8 bytes misaligned.
+	sfi_sp sub sp, #(FRAMESIZE - 8)
+	cfi_def_cfa_offset (FRAMESIZE)
+
+	@ Store the argument registers in La_arm_regs.
+	strd r0, r1, [sp, #LA_ARM_REGS]
+	cfi_offset (r0, LA_ARM_REGS + 0)
+	cfi_offset (r1, LA_ARM_REGS + 4)
+	strd r2, r3, [sp, #(LA_ARM_REGS + 8)]
+	cfi_offset (r2, LA_ARM_REGS + 8)
+	cfi_offset (r3, LA_ARM_REGS + 12)
+
+	ldr ip, [sp, #(FRAMESIZE - 8)]		@ ip gets &GOT[2]
+	ldr r3, [sp, #(FRAMESIZE - 4)]		@ r3 gets &GOT[n+3]
+
+	@ Recover the incoming sp and lr and save those in La_arm_regs.
+	add r0, sp, #FRAMESIZE
+	mov r1, lr
+	strd r0, r1, [sp, #(LA_ARM_REGS + 16)]
+	cfi_offset (sp, LA_ARM_REGS + 16)
+	cfi_offset (lr, LA_ARM_REGS + 20)
+
+	@ Get the 'struct link_map *' for the first arg to _dl_profile_fixup.
+	sfi_breg ip, ldr r0, [\B, #-4]
+
+	@ Get the reloc offset for the second argument to _dl_profile_fixup.
+	compute_reloc_arg r3, ip
+
+	@ The third argument is the original return address, still in lr.
+	mov r2, lr
+
+	@ Compute the fourth argument, the La_arm_regs pointer.
+	add r3, sp, #PLTEXIT_ARGS
+
+	@ Compute the fifth argument, the address of the 'framesize'
+	@ out parameter, and store it at the top of the stack.
+	add ip, sp, #PLTENTER_FRAMESIZE
+	str ip, [sp]
+
+	@ Save away the first two arguments, which we will need
+	@ again for _dl_call_pltexit, below.
+	strd r0, r1, [sp, #PLTEXIT_ARGS]
+
+	@ This does the real work, and returns the real call target.
+	sfi_bl _dl_profile_fixup
+
+	@ The address to call is now in r0.
+
+	@ Check whether we're wrapping this function,
+	@ i.e. if the framesize out parameter is >= 0.
+	ldr	ip, [sp, #PLTENTER_FRAMESIZE]
+	cmp	ip, #0
+	bge	1f
+	cfi_remember_state
+
+	@ Save _dl_profile_fixup's return value: the real call target.
+	mov ip, r0
+
+	@ Restore the registers from the La_arm_regs (perhaps as modified
+	@ by audit modules' pltenter functions).
+	add r1, sp, #LA_ARM_REGS
+	sfi_sp sfi_breg r1, ldmia \B, {r0-r3, sp, lr}
+	cfi_def_cfa_offset (0)
+	cfi_restore (r0)
+	cfi_restore (r1)
+	cfi_restore (r2)
+	cfi_restore (r3)
+	cfi_restore (sp)
+	cfi_restore (lr)
+
+	@ Finally, jump to the newfound call target.
+	sfi_bx ip
+
+1:	cfi_restore_state
+	@ The new frame size is in ip.
+
+	@ Save the fp in the stack slot previously used for the fifth
+	@ argument to _dl_profile_fixup.
+	str fp, [sp]
+	cfi_offset (fp, 0)
+
+	@ Save the result of _dl_profile_fixup, the real call target.
+	@ We'll reuse the stack slot just used for the 'framesize'
+	@ out parameter to _dl_profile_fixup.
+	str r0, [sp, #PLTENTER_FRAMESIZE]
+
+	@ Stack layout:
+	@ fp + 264		call target
+	@ fp + 72		La_arm_regs
+	@ fp + 68		Saved two arguments to _dl_profile_fixup
+	@ fp + 64		saved fp
+	@ fp + 0		La_arm_retval
+	@ sp..fp		copied incoming stack space (plus alignment)
+	@ For now, we only save the general purpose registers.
+# define FP_LA_ARM_RETVAL	0
+# define LA_ARM_RETVAL_SIZE	(4 * (4 + 12))
+# define FP_SAVED_FP		LA_ARM_RETVAL_SIZE
+# define FP_PLTEXIT_ARGS	(FP_SAVED_FP + 4)
+# define FP_LA_ARM_REGS		(FP_PLTEXIT_ARGS + 8)
+# define FP_CALL_TARGET		(FP_LA_ARM_REGS + LA_ARM_REGS_SIZE)
+# define FP_FRAMESIZE		(FP_CALL_TARGET + 4)
+
+	sub fp, sp, #(FP_FRAMESIZE - FRAMESIZE)
+	cfi_def_cfa (fp, FP_FRAMESIZE)
+
+	sub r1, fp, ip
+	@ This doesn't need sfi_sp because we just include the
+	@ sandboxing mask along with the alignment mask.
+	bic sp, r1, #0xc000000f
+
+	@ Copy the stack arguments.  The audit modules' pltenter
+	@ function(s) decided how much needs to be copied.
+	@ Load the sp as modified by pltenter functions, rather
+	@ than what we think the incoming sp was (fp + FP_FRAMESIZE).
+	sfi_breg fp, ldr r1, [\B, #(FP_LA_ARM_REGS + 16)]
+	mov r0, sp
+	mov r2, ip
+	sfi_bl memcpy
+
+	@ Load up the arguments from La_arm_regs and call the user's function.
+	sfi_breg fp, ldr ip, [\B, #FP_CALL_TARGET]
+	sfi_breg fp, ldrd r0, r1, [\B, #FP_LA_ARM_REGS]
+	sfi_breg fp, ldrd r2, r3, [\B, #(FP_LA_ARM_REGS + 8)]
+	sfi_blx ip
+
+	@ Stash the return value registers in La_arm_retval.
+	sfi_breg fp, strd r0, r1, [\B, #FP_LA_ARM_RETVAL]
+	sfi_breg fp, strd r2, r3, [\B, #(FP_LA_ARM_RETVAL + 8)]
+
+	@ Call pltexit.  We saved the first two arguments earlier--they
+	@ are the same ones passed to _dl_profile_fixup.  The latter two
+	@ arguments are La_arm_regs and La_arm_retval blocks, respectively.
+	sfi_breg fp, ldrd r0, r1, [\B, #FP_PLTEXIT_ARGS]
+	add r2, fp, #FP_LA_ARM_REGS
+	add r3, fp, #FP_LA_ARM_RETVAL
+	sfi_bl _dl_call_pltexit
+
+	@ Reload the saved return value registers for the caller.
+	sfi_breg fp, ldrd r0, r1, [\B, #FP_LA_ARM_RETVAL]
+	sfi_breg fp, ldrd r2, r3, [\B, #(FP_LA_ARM_RETVAL + 8)]
+
+	@ Unwind the frame.
+	sfi_sp mov sp, fp
+	cfi_def_cfa_register (sp)
+	ldr fp, [sp, #FP_SAVED_FP]
+	cfi_restore (fp)
+	@ Reload the lr and sp values from La_arm_regs, where they
+	@ might have been modified by pltenter functions, rather than
+	@ computing what we think the incoming value was.
+	ldr lr, [sp, #(FP_LA_ARM_REGS + 20)]
+	cfi_restore (lr)
+	sfi_sp ldr sp, [sp, #(FP_LA_ARM_REGS + 16)]
+	cfi_def_cfa_offset (0)
+
+	@ Finally, return to the caller.
+	sfi_bx lr
+
+	cfi_endproc
+	.size _dl_runtime_profile, .-_dl_runtime_profile
+#endif
+	.previous
diff --git a/sysdeps/arm/nacl/include/bits/setjmp.h b/sysdeps/arm/nacl/include/bits/setjmp.h
new file mode 100644
index 0000000000..41830e5c79
--- /dev/null
+++ b/sysdeps/arm/nacl/include/bits/setjmp.h
@@ -0,0 +1,38 @@
+/* Private jmp_buf-related definitions.  NaCl/ARM version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _INCLUDE_BITS_SETJMP_H
+#define _INCLUDE_BITS_SETJMP_H 1
+
+#ifndef __ASSEMBLER__
+/* Get the public declarations.  */
+# include <sysdeps/arm/bits/setjmp.h>
+#endif
+
+/* Register list for a ldm/stm instruction to load/store
+   the general registers from a __jmp_buf.
+
+   The generic ARM definition includes r9 (v6), which is not
+   permitted under NaCl.  We add r3 even though it's call-clobbered,
+   just to keep the size the same as the generic version.  */
+#define JMP_BUF_REGLIST		{r3, v1-v5, sl, fp}
+
+/* Index of __jmp_buf where the sp register resides.  */
+#define __JMP_BUF_SP		0
+
+#endif  /* include/bits/setjmp.h */
diff --git a/sysdeps/arm/nacl/shlib-versions b/sysdeps/arm/nacl/shlib-versions
new file mode 100644
index 0000000000..9d94784282
--- /dev/null
+++ b/sysdeps/arm/nacl/shlib-versions
@@ -0,0 +1,4 @@
+# Library=version		Earliest symbol set (optional)
+# ---------------		------------------------------
+
+ld=ld-nacl-arm.so.1
diff --git a/sysdeps/arm/nacl/start.c b/sysdeps/arm/nacl/start.c
new file mode 100644
index 0000000000..25f6fd774a
--- /dev/null
+++ b/sysdeps/arm/nacl/start.c
@@ -0,0 +1 @@
+#include <sysdeps/nacl/start.c>
diff --git a/sysdeps/arm/nacl/sysdep.h b/sysdeps/arm/nacl/sysdep.h
new file mode 100644
index 0000000000..951df3215d
--- /dev/null
+++ b/sysdeps/arm/nacl/sysdep.h
@@ -0,0 +1,69 @@
+/* Assembler macros for ARM/NaCl.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _ARM_NACL_SYSDEP_H
+#define _ARM_NACL_SYSDEP_H	1
+
+#ifdef __ASSEMBLER__
+
+# ifndef NO_THUMB
+#  define NO_THUMB
+# endif
+# define ARM_SFI_MACROS		1
+
+/* The compiler driver primes the assembler with a standard set of
+   macros that includes sfi_breg and sfi_sp.  The sfi_pld macro is
+   redundant with sfi_breg, but libc code uses it so as not to run
+   afoul of the assembler's parsing bug in versions prior to 2.23.2.
+   NaCl never uses an assembler that has this bug.  */
+
+.macro sfi_pld basereg, offset=#0
+	sfi_breg \basereg, pld [\basereg, \offset]
+.endm
+
+#endif
+
+#include <sysdeps/arm/sysdep.h>
+
+#ifdef  __ASSEMBLER__
+
+# undef eabi_fnstart
+# define eabi_fnstart
+# undef eabi_fnend
+# define eabi_fnend
+# undef eabi_save
+# define eabi_save(...)
+# undef eabi_cantunwind
+# define eabi_cantunwind
+# undef eabi_pad
+# define eabi_pad(n)
+
+/* NaCl has its own special way of getting the thread pointer.  */
+# undef	GET_TLS
+# define GET_TLS(tmp)		ldr r0, [r9]
+
+/* Rather than macroizing the code any more, we can just define a few
+   mnemonics as macros here.  */
+# define bl			sfi_bl
+# define bx			sfi_bx
+# define blx			sfi_blx
+# define bxeq			sfi_bxeq /* Only condition now in use.  */
+
+#endif  /* __ASSEMBLER__ */
+
+#endif  /* sysdep.h */
diff --git a/sysdeps/arm/nacl/tls.h b/sysdeps/arm/nacl/tls.h
new file mode 100644
index 0000000000..646e7a9d06
--- /dev/null
+++ b/sysdeps/arm/nacl/tls.h
@@ -0,0 +1,2 @@
+#include <sysdeps/arm/nptl/tls.h>
+#include <sysdeps/nacl/tls.h>
diff --git a/sysdeps/nacl/Implies b/sysdeps/nacl/Implies
new file mode 100644
index 0000000000..0448f3f018
--- /dev/null
+++ b/sysdeps/nacl/Implies
@@ -0,0 +1,3 @@
+nptl
+posix
+gnu
diff --git a/sysdeps/nacl/Makefile b/sysdeps/nacl/Makefile
new file mode 100644
index 0000000000..b51156b5ad
--- /dev/null
+++ b/sysdeps/nacl/Makefile
@@ -0,0 +1,135 @@
+# Makefile fragment for NaCl configurations.
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+# The libthread_db code does not compile for NaCl because there is no
+# sys/procfs.h supplying the register layout types.  But since libthread_db
+# will probably never be useful for NaCl, just elide the directory rather
+# than implementing stuff to make it compile (and never get used).
+subdirs := $(filter-out nptl_db,$(subdirs))
+sorted-subdirs := $(filter-out nptl_db,$(sorted-subdirs))
+
+# The (required) --with-headers option to configure sets sysheaders to the
+# location of the native_client/.. source directory.  We'll get necessary
+# headers directly from there.
+naclsrc = $(sysheaders)/native_client/src
+
+# How to find the directory containing this Makefile.
+nacl = $(..)sysdeps/nacl
+
+# Generate our bits/errno.h with the numbers from NaCl's sys/errno.h file.
+nacl-errno = $(naclsrc)/trusted/service_runtime/include/sys/errno.h
+
+bits-errno = $(common-objpfx)bits/errno.h
+$(bits-errno): $(common-objpfx)stamp-errnos ;
+$(common-objpfx)stamp-errnos: $(nacl)/errnos.awk $(..)manual/errno.texi \
+			      $(nacl-errno)
+	$(make-target-directory)
+	$(AWK) -f $^ > $(bits-errno)-tmp
+# Make it unwritable so noone will edit it by mistake.
+	-chmod a-w $(bits-errno)-tmp
+	$(move-if-change) $(bits-errno)-tmp $(bits-errno)
+	touch $@
+common-generated += stamp-errnos bits/errno.h
+before-compile += $(bits-errno)
+
+# Massage NaCl's irt.h (and irt_dev.h) into something we can use.
+# See irt.sed for details.
+nacl-irt.h = $(common-objpfx)nacl-irt.h
+$(nacl-irt.h): $(nacl)/irt.sed \
+	       $(naclsrc)/untrusted/irt/irt.h \
+	       $(naclsrc)/untrusted/irt/irt_dev.h
+	sed -f $^ > $@.new
+	mv -f $@.new $@
+common-generated += nacl-irt.h
+before-compile += $(nacl-irt.h)
+
+$(common-objpfx)nacl-interfaces.v.i: $(nacl)/nacl-interfaces.mk.in \
+				     $(nacl)/nacl-interface-list.h
+-include $(common-objpfx)nacl-interfaces.v
+common-generated += nacl-interfaces.v
+before-compile += $(common-objpfx)nacl-interfaces.v
+
+nacl-all-interfaces = $(nacl-mandatory-interfaces) $(nacl-optional-interfaces)
+nacl-interface-routines = $(nacl-all-interfaces:%=nacl-interface-%)
+
+define nacl-interface-table-command
+(echo '#define INTERFACE_CATEGORY $1'; \
+ echo '#define INTERFACE_MODULE $(firstword $(subst -, ,$*))'; \
+ echo '#define INTERFACE_TYPE $(word 2,$(subst -, ,$*))'; \
+ echo '#define INTERFACE_STRING $(nacl-$*-string)'; \
+ echo '#include "nacl-interface-table.c"' \
+) > $@T
+mv -f $@T $@
+endef
+
+nacl-interface-pattern = $(objpfx)nacl-interface-%.c
+
+$(nacl-mandatory-interfaces:%=$(nacl-interface-pattern)): \
+  $(nacl-interface-pattern): $(nacl)/Makefile $(common-objpfx)nacl-interfaces.v
+	$(make-target-directory)
+	$(call nacl-interface-table-command,mandatory)
+$(nacl-optional-interfaces:%=$(nacl-interface-pattern)): \
+  $(nacl-interface-pattern): $(nacl)/Makefile $(common-objpfx)nacl-interfaces.v
+	$(make-target-directory)
+	$(call nacl-interface-table-command,optional)
+
+nacl-routines-of = $(filter nacl-interface-$1-%,$(nacl-interface-routines))
+
+
+# Run the NaCl code validator on binaries after we link them, so the
+# build does not succeed with any binary that won't pass validation.
+# Moving the file around makes sure that we don't leave a target
+# appearing complete after it fails validation.
+define after-link
+mv -f $1 $1.prevalidation
+$(nacl)/nacl-after-link.sh '${READELF}' $1.prevalidation
+mv -f $1.prevalidation $1
+endef
+
+# The test wrapper script takes care of running things under NaCl's sel_ldr.
+test-wrapper-env-only = $(nacl)/nacl-test-wrapper.sh --arch=$(nacl-sdk-arch)
+test-wrapper-env = $(test-wrapper-env-only)
+test-wrapper = $(test-wrapper-env) --
+
+ifeq ($(subdir),csu)
+sysdep_routines += nacl_interface_query \
+		   nacl-interfaces $(call nacl-routines-of,libc)
+endif
+
+ifeq ($(subdir),elf)
+sysdep-dl-routines += $(call nacl-routines-of,rtld)
+sysdep-rtld-routines += nacl-interfaces $(call nacl-routines-of,rtld)
+endif
+
+ifeq ($(subdir),io)
+sysdep_routines += xstatconv
+endif
+
+ifeq ($(subdir),nptl)
+# We do not need any wrappers in libpthread.
+libpthread-routines := $(filter-out ptw-%,$(libpthread-routines))
+endif
+
+ifeq ($(subdir),misc)
+# We reuse the Linux file since the bits match.  The file lives in the
+# top-level source tree so we can use it without reference to any
+# sysdeps/.../linux/ directories, but it's still a sysdeps decision to
+# install it.
+sysdep_headers += bits/mman-linux.h
+endif
diff --git a/sysdeps/nacl/Subdirs b/sysdeps/nacl/Subdirs
new file mode 100644
index 0000000000..5d570b9969
--- /dev/null
+++ b/sysdeps/nacl/Subdirs
@@ -0,0 +1,3 @@
+inet
+resolv
+nss
diff --git a/sysdeps/nacl/Versions b/sysdeps/nacl/Versions
new file mode 100644
index 0000000000..4ac56c2a28
--- /dev/null
+++ b/sysdeps/nacl/Versions
@@ -0,0 +1,21 @@
+ld {
+  GLIBC_PRIVATE {
+    __nacl_irt_*;
+  }
+}
+
+libc {
+  GLIBC_2.22 {
+    nacl_interface_query;
+  }
+
+  GLIBC_PRIVATE {
+    # These are used by libpthread.
+    __libc_write;
+    __libc_open;
+    __libc_close;
+    __libc_fork;
+
+    __nacl_irt_*;
+  }
+}
diff --git a/sysdeps/nacl/_exit.c b/sysdeps/nacl/_exit.c
new file mode 100644
index 0000000000..6006e26e55
--- /dev/null
+++ b/sysdeps/nacl/_exit.c
@@ -0,0 +1,34 @@
+/* _exit -- low-level program termination.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <nacl-interfaces.h>
+
+void
+_exit (int status)
+{
+  __nacl_irt_basic.exit (status);
+
+  /* That never returns unless something is severely and unrecoverably wrong.
+     If it ever does, try to make sure we crash.  */
+  while (1)
+    __builtin_trap ();
+}
+libc_hidden_def (_exit)
+weak_alias (_exit, _Exit)
diff --git a/sysdeps/nacl/access.c b/sysdeps/nacl/access.c
new file mode 100644
index 0000000000..531a999c01
--- /dev/null
+++ b/sysdeps/nacl/access.c
@@ -0,0 +1,28 @@
+/* Check file access permission.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Test for access to FILE.  */
+int
+__access (const char *file, int type)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.access (file, type), 0);
+}
+weak_alias (__access, access)
diff --git a/sysdeps/nacl/backtrace.c b/sysdeps/nacl/backtrace.c
new file mode 100644
index 0000000000..27ce597b39
--- /dev/null
+++ b/sysdeps/nacl/backtrace.c
@@ -0,0 +1 @@
+#include <sysdeps/x86_64/backtrace.c>
diff --git a/sysdeps/nacl/bits/dirent.h b/sysdeps/nacl/bits/dirent.h
new file mode 100644
index 0000000000..571ac0c67b
--- /dev/null
+++ b/sysdeps/nacl/bits/dirent.h
@@ -0,0 +1,52 @@
+/* Directory entry structure `struct dirent'.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _DIRENT_H
+# error "Never use <bits/dirent.h> directly; include <dirent.h> instead."
+#endif
+
+/* Note that __ino_t and __ino64_t are the same type.
+   Likewise __off_t and __off64_t are the same type.  */
+
+struct dirent
+  {
+    __ino_t d_ino;		/* File serial number.  */
+    __off_t d_off;		/* File position of this entry.  */
+    unsigned short int d_reclen; /* Length of the whole `struct dirent'.  */
+
+    /* Only this member is in the POSIX standard.  */
+    char d_name[256];		/* We must not include limits.h! */
+  };
+
+#ifdef __USE_LARGEFILE64
+/* This is completely identical to `struct dirent'.  */
+struct dirent64
+  {
+    __ino_t d_ino;		/* File serial number.  */
+    __off_t d_off;		/* File position of this entry.  */
+    unsigned short int d_reclen; /* Length of the whole `struct dirent'.  */
+
+    /* Only this member is in the POSIX standard.  */
+    char d_name[256];		/* We must not include limits.h! */
+  };
+#endif
+
+#define d_fileno			d_ino /* Backwards compatibility.  */
+
+#define _DIRENT_HAVE_D_RECLEN		1
+#define _DIRENT_MATCHES_DIRENT64	1
diff --git a/sysdeps/nacl/bits/fcntl.h b/sysdeps/nacl/bits/fcntl.h
new file mode 100644
index 0000000000..ceef8dfeab
--- /dev/null
+++ b/sysdeps/nacl/bits/fcntl.h
@@ -0,0 +1,149 @@
+/* O_*, F_*, FD_* bit values.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _FCNTL_H
+#error "Never use <bits/fcntl.h> directly; include <fcntl.h> instead."
+#endif
+
+
+/* File access modes for `open' and `fcntl'.  */
+#define O_RDONLY        0       /* Open read-only.  */
+#define O_WRONLY        1       /* Open write-only.  */
+#define O_RDWR          2       /* Open read/write.  */
+
+
+/* Bits OR'd into the second argument to open.  */
+#define O_CREAT         00100   /* Create file if it doesn't exist.  */
+#define O_EXCL          00200   /* Fail if file already exists.  */
+#define O_TRUNC         01000   /* Truncate file to zero length.  */
+#define O_NOCTTY        0       /* Don't assign a controlling terminal.  */
+#define O_ASYNC         020000  /* Send SIGIO to owner when data is ready.  */
+#define O_FSYNC         010000  /* Synchronous writes.  */
+#define O_SYNC          O_FSYNC
+#ifdef  __USE_MISC
+# define O_SHLOCK       XXX     /* Open with shared file lock.  */
+# define O_EXLOCK       XXX     /* Open with shared exclusive lock.  */
+#endif
+#ifdef __USE_XOPEN2K8
+# define O_DIRECTORY    00200000        /* Must be a directory.  */
+# define O_NOFOLLOW     00400000        /* Do not follow links.  */
+# define O_CLOEXEC      02000000        /* Set close_on_exec.  */
+#endif
+#if defined __USE_POSIX199309 || defined __USE_UNIX98
+# define O_DSYNC        O_SYNC          /* Synchronize data.  */
+# define O_RSYNC        O_SYNC          /* Synchronize read operations.  */
+#endif
+
+/* All opens support large file sizes, so there is no flag bit for this.  */
+#ifdef __USE_LARGEFILE64
+# define O_LARGEFILE    0
+#endif
+
+/* File status flags for `open' and `fcntl'.  */
+#define O_APPEND        02000   /* Writes append to the file.  */
+#define O_NONBLOCK      04000   /* Non-blocking I/O.  */
+
+#ifdef __USE_MISC
+# define O_NDELAY       O_NONBLOCK
+#endif
+
+#ifdef __USE_MISC
+/* Bits in the file status flags returned by F_GETFL.
+   These are all the O_* flags, plus FREAD and FWRITE, which are
+   independent bits set by which of O_RDONLY, O_WRONLY, and O_RDWR, was
+   given to `open'.  */
+# define FREAD          1
+# define FWRITE         2
+
+/* Traditional BSD names the O_* bits.  */
+# define FASYNC         O_ASYNC
+# define FFSYNC         O_FSYNC
+# define FSYNC          O_SYNC
+# define FAPPEND        O_APPEND
+# define FNDELAY        O_NDELAY
+#endif
+
+/* Mask for file access modes.  This is system-dependent in case
+   some system ever wants to define some other flavor of access.  */
+#define O_ACCMODE       (O_RDONLY|O_WRONLY|O_RDWR)
+
+/* Values for the second argument to `fcntl'.  */
+#define F_DUPFD         0       /* Duplicate file descriptor.  */
+#define F_GETFD         1       /* Get file descriptor flags.  */
+#define F_SETFD         2       /* Set file descriptor flags.  */
+#define F_GETFL         3       /* Get file status flags.  */
+#define F_SETFL         4       /* Set file status flags.  */
+#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
+#define F_GETOWN        5       /* Get owner (receiver of SIGIO).  */
+#define F_SETOWN        6       /* Set owner (receiver of SIGIO).  */
+#endif
+#define F_GETLK         7       /* Get record locking info.  */
+#define F_SETLK         8       /* Set record locking info (non-blocking).  */
+#define F_SETLKW        9       /* Set record locking info (blocking).  */
+/* Not necessary, we always have 64-bit offsets.  */
+#define F_GETLK64       F_GETLK /* Get record locking info.  */
+#define F_SETLK64       F_SETLK /* Set record locking info (non-blocking).  */
+#define F_SETLKW64      F_SETLKW/* Set record locking info (blocking).  */
+#ifdef __USE_XOPEN2K8
+# define F_DUPFD_CLOEXEC 12     /* Duplicate file descriptor with
+                                   close-on-exec set.  */
+#endif
+
+/* File descriptor flags used with F_GETFD and F_SETFD.  */
+#define FD_CLOEXEC      1       /* Close on exec.  */
+
+
+#include <bits/types.h>
+
+/* The structure describing an advisory lock.  This is the type of the third
+   argument to `fcntl' for the F_GETLK, F_SETLK, and F_SETLKW requests.  */
+struct flock
+  {
+    short int l_type;   /* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.  */
+    short int l_whence; /* Where `l_start' is relative to (like `lseek').  */
+    __off_t l_start;    /* Offset where the lock begins.  */
+    __off_t l_len;      /* Size of the locked area; zero means until EOF.  */
+    __pid_t l_pid;      /* Process holding the lock.  */
+  };
+
+#ifdef __USE_LARGEFILE64
+/* Note this matches struct flock exactly.  */
+struct flock64
+  {
+    short int l_type;   /* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.  */
+    short int l_whence; /* Where `l_start' is relative to (like `lseek').  */
+    __off_t l_start;    /* Offset where the lock begins.  */
+    __off_t l_len;      /* Size of the locked area; zero means until EOF.  */
+    __pid_t l_pid;      /* Process holding the lock.  */
+  };
+#endif
+
+/* Values for the `l_type' field of a `struct flock'.  */
+#define F_RDLCK 1       /* Read lock.  */
+#define F_WRLCK 2       /* Write lock.  */
+#define F_UNLCK 3       /* Remove lock.  */
+
+/* Advice to `posix_fadvise'.  */
+#ifdef __USE_XOPEN2K
+# define POSIX_FADV_NORMAL      0 /* No further special treatment.  */
+# define POSIX_FADV_RANDOM      1 /* Expect random page references.  */
+# define POSIX_FADV_SEQUENTIAL  2 /* Expect sequential page references.  */
+# define POSIX_FADV_WILLNEED    3 /* Will need these pages.  */
+# define POSIX_FADV_DONTNEED    4 /* Don't need these pages.  */
+# define POSIX_FADV_NOREUSE     5 /* Data will be accessed once.  */
+#endif
diff --git a/sysdeps/nacl/bits/local_lim.h b/sysdeps/nacl/bits/local_lim.h
new file mode 100644
index 0000000000..950a2371e0
--- /dev/null
+++ b/sysdeps/nacl/bits/local_lim.h
@@ -0,0 +1,64 @@
+/* Minimum guaranteed maximum values for system limits.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#define NAME_MAX        255
+
+#define PATH_MAX        4096
+
+#define NGROUPS_MAX    65536
+
+/* The number of data keys per process.  */
+#define _POSIX_THREAD_KEYS_MAX  128
+/* This is the value this implementation supports.  */
+#define PTHREAD_KEYS_MAX        1024
+
+/* Controlling the iterations of destructors for thread-specific data.  */
+#define _POSIX_THREAD_DESTRUCTOR_ITERATIONS     4
+/* Number of iterations this implementation does.  */
+#define PTHREAD_DESTRUCTOR_ITERATIONS   _POSIX_THREAD_DESTRUCTOR_ITERATIONS
+
+/* The number of threads per process.  */
+#define _POSIX_THREAD_THREADS_MAX       64
+/* We have no predefined limit on the number of threads.  */
+#undef PTHREAD_THREADS_MAX
+
+/* Maximum amount by which a process can descrease its asynchronous I/O
+   priority level.  */
+#define AIO_PRIO_DELTA_MAX      20
+
+/* Minimum size for a thread.  We are free to choose a reasonable value.  */
+#define PTHREAD_STACK_MIN       131072
+
+/* Maximum number of timer expiration overruns.  */
+#define DELAYTIMER_MAX          2147483647
+
+/* Maximum tty name length.  */
+#define TTY_NAME_MAX            32
+
+/* Maximum login name length.  This is arbitrary.  */
+#define LOGIN_NAME_MAX          256
+
+/* Maximum host name length.  */
+#define HOST_NAME_MAX           64
+
+/* Maximum message queue priority level.  */
+#define MQ_PRIO_MAX             32768
+
+/* Maximum value the semaphore can have.  */
+#define SEM_VALUE_MAX           (2147483647)
diff --git a/sysdeps/nacl/bits/mman.h b/sysdeps/nacl/bits/mman.h
new file mode 100644
index 0000000000..2d5fdfc17b
--- /dev/null
+++ b/sysdeps/nacl/bits/mman.h
@@ -0,0 +1,24 @@
+/* Definitions for POSIX memory map interface.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_MMAN_H
+# error "Never use <bits/mman.h> directly; include <sys/mman.h> instead."
+#endif
+
+/* NaCl uses the Linux bits for this.  */
+#include <bits/mman-linux.h>
diff --git a/sysdeps/nacl/bits/param.h b/sysdeps/nacl/bits/param.h
new file mode 100644
index 0000000000..17eb1ee43f
--- /dev/null
+++ b/sysdeps/nacl/bits/param.h
@@ -0,0 +1,23 @@
+/* Old-style Unix parameters and limits.  NaCl version.
+   Copyright (C) 2012 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_PARAM_H
+# error "Never use <bits/param.h> directly; include <sys/param.h> instead."
+#endif
+
+#define EXEC_PAGESIZE   0x10000
diff --git a/sysdeps/nacl/bits/posix_opt.h b/sysdeps/nacl/bits/posix_opt.h
new file mode 100644
index 0000000000..2a5d6fd70a
--- /dev/null
+++ b/sysdeps/nacl/bits/posix_opt.h
@@ -0,0 +1,210 @@
+/* Define POSIX options for NaCl.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef	_BITS_POSIX_OPT_H
+#define	_BITS_POSIX_OPT_H	1
+
+/* Job control is supported.  (Not really, but the APIs exist.)  */
+#define	_POSIX_JOB_CONTROL			1
+
+/* Processes have a saved set-user-ID and a saved set-group-ID.  */
+#define	_POSIX_SAVED_IDS			1
+
+/* Priority scheduling is supported. ??? */
+#define	_POSIX_PRIORITY_SCHEDULING		200809L
+
+/* Synchronizing file data is supported. ???  */
+#define	_POSIX_SYNCHRONIZED_IO			200809L
+
+/* The fsync function is present.  */
+#define	_POSIX_FSYNC				200809L
+
+/* Mapping of files to memory is supported.  */
+#define	_POSIX_MAPPED_FILES			200809L
+
+/* Locking of all memory is not supported.  */
+#define	_POSIX_MEMLOCK				-1
+
+/* Locking of ranges of memory is not supported.  */
+#define	_POSIX_MEMLOCK_RANGE			-1
+
+/* Setting of memory protections is supported.  */
+#define	_POSIX_MEMORY_PROTECTION		200809L
+
+/* Some filesystems allow all users to change file ownership.  */
+#define	_POSIX_CHOWN_RESTRICTED			0
+
+/* `c_cc' member of 'struct termios' structure can be disabled by
+   using the value _POSIX_VDISABLE.  ??? */
+#define	_POSIX_VDISABLE				'\0'
+
+/* Filenames are not silently truncated.  */
+#define	_POSIX_NO_TRUNC				1
+
+/* X/Open realtime support is not fully available.  This requires the
+   following set of POSIX.1 features, not all of which NaCl supports:
+        _POSIX_FSYNC
+        _POSIX_MEMLOCK
+        _POSIX_MEMLOCK_RANGE
+        _POSIX_MESSAGE_PASSING
+        _POSIX_PRIORITIZED_IO
+        _POSIX_PRIORITY_SCHEDULING
+        _POSIX_SHARED_MEMORY_OBJECTS
+        _POSIX_SYNCHRONIZED_IO
+ */
+#define _XOPEN_REALTIME				-1
+
+/* X/Open thread realtime support is not available.  This requires the
+   following set of POSIX.1 features, none of which NaCl supports:
+        _POSIX_THREAD_PRIO_INHERIT
+        _POSIX_THREAD_PRIO_PROTECT
+        _POSIX_THREAD_PRIORITY_SCHEDULING
+        _POSIX_THREAD_ROBUST_PRIO_INHERIT
+        _POSIX_THREAD_ROBUST_PRIO_PROTECT
+ */
+#define _XOPEN_REALTIME_THREADS			-1
+
+/* XPG4.2 shared memory is not supported.
+   ??? What is this?  shm* interfaces?
+*/
+#define	_XOPEN_SHM				-1
+
+/* POSIX threads are supported.  */
+#define _POSIX_THREADS				200809L
+
+/* We have the reentrant functions described in POSIX.  */
+#define _POSIX_REENTRANT_FUNCTIONS      	1
+#define _POSIX_THREAD_SAFE_FUNCTIONS		200809L
+
+/* We do not provide priority scheduling for threads.  */
+#define _POSIX_THREAD_PRIORITY_SCHEDULING	-1
+
+/* We support user-defined stack sizes.  */
+#define _POSIX_THREAD_ATTR_STACKSIZE		200809L
+
+/* We support user-defined stacks.  */
+#define _POSIX_THREAD_ATTR_STACKADDR		200809L
+
+/* We do not support priority inheritence.  */
+#define _POSIX_THREAD_PRIO_INHERIT		-1
+
+/* We do not support priority protection.  */
+#define _POSIX_THREAD_PRIO_PROTECT		-1
+
+#ifdef __USE_XOPEN2K8
+/* We do not support priority inheritence for robust mutexes.  */
+# define _POSIX_THREAD_ROBUST_PRIO_INHERIT	-1
+
+/* We do not support priority protection for robust mutexes.  */
+# define _POSIX_THREAD_ROBUST_PRIO_PROTECT	-1
+#endif
+
+/* We support POSIX.1b semaphores.  */
+#define _POSIX_SEMAPHORES			200809L
+
+/* Real-time signals are supported. ???  */
+#define _POSIX_REALTIME_SIGNALS			200809L
+
+/* We support asynchronous I/O.  */
+#define _POSIX_ASYNCHRONOUS_IO			200809L
+#define _POSIX_ASYNC_IO				1
+/* Alternative name for Unix98.  */
+#define _LFS_ASYNCHRONOUS_IO			1
+/* Support for prioritization is not available.  */
+#define _POSIX_PRIORITIZED_IO			-1
+
+/* The LFS support in asynchronous I/O is also available.  */
+#define _LFS64_ASYNCHRONOUS_IO			1
+
+/* The rest of the LFS is also available.  */
+#define _LFS_LARGEFILE				1
+#define _LFS64_LARGEFILE			1
+#define _LFS64_STDIO				1
+
+/* POSIX shared memory objects are implemented.  */
+#define _POSIX_SHARED_MEMORY_OBJECTS		200809L
+
+/* Process CPU-time clocks are not supported.  */
+#define _POSIX_CPUTIME				-1
+
+/* Thread CPU-time locks are supported.  */
+#define _POSIX_THREAD_CPUTIME			200809L
+
+/* GNU libc provides regular expression handling.  */
+#define _POSIX_REGEXP				1
+
+/* Reader/Writer locks are available.  */
+#define _POSIX_READER_WRITER_LOCKS		200809L
+
+/* We have a POSIX shell.  */
+#define _POSIX_SHELL				1
+
+/* We support the Timeouts option.  */
+#define _POSIX_TIMEOUTS				200809L
+
+/* We support spinlocks.  */
+#define _POSIX_SPIN_LOCKS			200809L
+
+/* The `spawn' function family is supported.  */
+#define _POSIX_SPAWN				200809L
+
+/* We have POSIX timers.  */
+#define _POSIX_TIMERS				200809L
+
+/* The barrier functions are available.  */
+#define _POSIX_BARRIERS				200809L
+
+/* POSIX message queues are not available.  */
+#define	_POSIX_MESSAGE_PASSING			-1
+
+/* Thread process-shared synchronization is not supported.  */
+#define _POSIX_THREAD_PROCESS_SHARED		-1
+
+/* The monotonic clock is available.  */
+#define _POSIX_MONOTONIC_CLOCK			200809L
+
+/* The clock selection interfaces are available.  ??? Actually only
+   clock_nanosleep works, and pthread_condattr_setclock does not.  */
+#define _POSIX_CLOCK_SELECTION			200809L
+
+/* Advisory information interfaces are available.  */
+#define _POSIX_ADVISORY_INFO			200809L
+
+/* IPv6 support is available.  */
+#define _POSIX_IPV6				200809L
+
+/* Raw socket support is available.  */
+#define _POSIX_RAW_SOCKETS			200809L
+
+/* We have at least one terminal.  */
+#define _POSIX2_CHAR_TERM			200809L
+
+/* Neither process nor thread sporadic server interfaces is available.  */
+#define _POSIX_SPORADIC_SERVER			-1
+#define _POSIX_THREAD_SPORADIC_SERVER		-1
+
+/* trace.h is not available.  */
+#define _POSIX_TRACE				-1
+#define _POSIX_TRACE_EVENT_FILTER		-1
+#define _POSIX_TRACE_INHERIT			-1
+#define _POSIX_TRACE_LOG			-1
+
+/* Typed memory objects are not available.  */
+#define _POSIX_TYPED_MEMORY_OBJECTS		-1
+
+#endif /* bits/posix_opt.h */
diff --git a/sysdeps/nacl/bits/stat.h b/sysdeps/nacl/bits/stat.h
new file mode 100644
index 0000000000..0cd3500adb
--- /dev/null
+++ b/sysdeps/nacl/bits/stat.h
@@ -0,0 +1,147 @@
+/* 'struct stat' and related definitions.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#if !defined _SYS_STAT_H && !defined _FCNTL_H
+# error "Never include <bits/stat.h> directly; use <sys/stat.h> instead."
+#endif
+
+#ifndef _BITS_STAT_H
+#define _BITS_STAT_H	1
+
+/* Versions of the `struct stat' data structure.  */
+#define _STAT_VER_NACL		0
+#define _STAT_VER_LINUX		1
+
+#define _STAT_VER		_STAT_VER_LINUX
+
+struct stat
+  {
+    __dev_t st_dev;		/* Device.  */
+    __ino_t st_ino;		/* File serial number.	*/
+    __nlink_t st_nlink;		/* Link count.  */
+    __mode_t st_mode;		/* File mode.  */
+    __uid_t st_uid;		/* User ID of the file's owner.	*/
+    __gid_t st_gid;		/* Group ID of the file's group.*/
+    int __pad0;
+    __dev_t st_rdev;		/* Device number, if device.  */
+    __off_t st_size;		/* Size of file, in bytes.  */
+    __blksize_t st_blksize;	/* Optimal block size for I/O.  */
+    __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
+#if defined __USE_MISC || defined __USE_XOPEN2K8
+    /* Nanosecond resolution timestamps are stored in a format
+       equivalent to 'struct timespec'.  This is the type used
+       whenever possible but the Unix namespace rules do not allow the
+       identifier 'timespec' to appear in the <sys/stat.h> header.
+       Therefore we have to handle the use of this header in strictly
+       standard-compliant sources special.  */
+    struct timespec st_atim;		/* Time of last access.  */
+    struct timespec st_mtim;		/* Time of last modification.  */
+    struct timespec st_ctim;		/* Time of last status change.  */
+# define st_atime st_atim.tv_sec	/* Backward compatibility.  */
+# define st_mtime st_mtim.tv_sec
+# define st_ctime st_ctim.tv_sec
+#else
+    __time_t st_atime;			/* Time of last access.  */
+    __uint64_t st_atimensec;            /* Nsecs of last access.  */
+    __time_t st_mtime;			/* Time of last modification.  */
+    __uint64_t st_mtimensec;            /* Nsecs of last modification.  */
+    __time_t st_ctime;			/* Time of last status change.  */
+    __uint64_t st_ctimensec;            /* Nsecs of last status change.  */
+#endif
+    __int64_t __unused[3];
+  };
+
+#ifdef __USE_LARGEFILE64
+/* Note stat64 has the same shape as stat for NaCl.  */
+struct stat64
+  {
+    __dev_t st_dev;		/* Device.  */
+    __ino_t st_ino;		/* File serial number.	*/
+    __nlink_t st_nlink;		/* Link count.  */
+    __mode_t st_mode;		/* File mode.  */
+    __uid_t st_uid;		/* User ID of the file's owner.	*/
+    __gid_t st_gid;		/* Group ID of the file's group.*/
+    int __pad0;
+    __dev_t st_rdev;		/* Device number, if device.  */
+    __off_t st_size;		/* Size of file, in bytes.  */
+    __blksize_t st_blksize;	/* Optimal block size for I/O.  */
+    __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
+# if defined __USE_MISC || defined __USE_XOPEN2K8
+    /* Nanosecond resolution timestamps are stored in a format
+       equivalent to 'struct timespec'.  This is the type used
+       whenever possible but the Unix namespace rules do not allow the
+       identifier 'timespec' to appear in the <sys/stat.h> header.
+       Therefore we have to handle the use of this header in strictly
+       standard-compliant sources special.  */
+    struct timespec st_atim;		/* Time of last access.  */
+    struct timespec st_mtim;		/* Time of last modification.  */
+    struct timespec st_ctim;		/* Time of last status change.  */
+#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
+#  define st_mtime st_mtim.tv_sec
+#  define st_ctime st_ctim.tv_sec
+# else
+    __time_t st_atime;			/* Time of last access.  */
+    __uint64_t st_atimensec;            /* Nsecs of last access.  */
+    __time_t st_mtime;			/* Time of last modification.  */
+    __uint64_t st_mtimensec;            /* Nsecs of last modification.  */
+    __time_t st_ctime;			/* Time of last status change.  */
+    __uint64_t st_ctimensec;            /* Nsecs of last status change.  */
+# endif
+    __int64_t __unused[3];
+  };
+#endif
+
+/* Tell code we have these members.  */
+#define	_STATBUF_ST_BLKSIZE	1
+#define _STATBUF_ST_RDEV	1
+/* Nanosecond resolution time values are supported.  */
+#define _STATBUF_ST_NSEC	1
+
+/* Encoding of the file mode.  */
+
+#define	__S_IFMT	0170000	/* These bits determine file type.  */
+
+/* File types.  */
+#define	__S_IFDIR	0040000	/* Directory.  */
+#define	__S_IFCHR	0020000	/* Character device.  */
+#define	__S_IFBLK	0060000	/* Block device.  */
+#define	__S_IFREG	0100000	/* Regular file.  */
+#define	__S_IFIFO	0010000	/* FIFO.  */
+#define	__S_IFLNK	0120000	/* Symbolic link.  */
+#define	__S_IFSOCK	0140000	/* Socket.  */
+
+/* POSIX.1b objects.  Note that these macros always evaluate to zero.  But
+   they do it by enforcing the correct use of the macros.  */
+#define __S_TYPEISMQ(buf)  ((buf)->st_mode - (buf)->st_mode)
+#define __S_TYPEISSEM(buf) ((buf)->st_mode - (buf)->st_mode)
+#define __S_TYPEISSHM(buf) ((buf)->st_mode - (buf)->st_mode)
+
+/* Protection bits.  */
+
+#define	__S_ISUID	04000	/* Set user ID on execution.  */
+#define	__S_ISGID	02000	/* Set group ID on execution.  */
+#define	__S_ISVTX	01000	/* Save swapped text after use (sticky).  */
+#define	__S_IREAD	0400	/* Read by owner.  */
+#define	__S_IWRITE	0200	/* Write by owner.  */
+#define	__S_IEXEC	0100	/* Execute by owner.  */
+
+#ifdef __USE_ATFILE
+/* XXX missing: UTIME_NOW, UTIME_OMIT */
+#endif
+
+#endif	/* bits/stat.h */
diff --git a/sysdeps/nacl/bits/typesizes.h b/sysdeps/nacl/bits/typesizes.h
new file mode 100644
index 0000000000..2a29035057
--- /dev/null
+++ b/sysdeps/nacl/bits/typesizes.h
@@ -0,0 +1,71 @@
+/* bits/typesizes.h -- underlying types for *_t.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _BITS_TYPES_H
+# error "Never include <bits/typesizes.h> directly; use <sys/types.h> instead."
+#endif
+
+#ifndef	_BITS_TYPESIZES_H
+#define	_BITS_TYPESIZES_H	1
+
+/* See <bits/types.h> for the meaning of these macros.  This file exists so
+   that <bits/types.h> need not vary across different GNU platforms.  */
+
+#define __DEV_T_TYPE		__UQUAD_TYPE
+#define __UID_T_TYPE		__U32_TYPE
+#define __GID_T_TYPE		__U32_TYPE
+#define __INO_T_TYPE		__UQUAD_TYPE
+#define __INO64_T_TYPE		__INO_T_TYPE
+#define __MODE_T_TYPE		__U32_TYPE
+#define __NLINK_T_TYPE		__UWORD_TYPE
+#define __OFF_T_TYPE		__SQUAD_TYPE
+#define __OFF64_T_TYPE		__OFF_T_TYPE
+#define __PID_T_TYPE		__S32_TYPE
+#define __RLIM_T_TYPE		__UQUAD_TYPE
+#define __RLIM64_T_TYPE		__RLIM_T_TYPE
+#define	__BLKCNT_T_TYPE		__SQUAD_TYPE
+#define	__BLKCNT64_T_TYPE	__BLKCNT_T_TYPE
+#define	__FSBLKCNT_T_TYPE	__UQUAD_TYPE
+#define	__FSBLKCNT64_T_TYPE	__FSBLKCNT_T_TYPE
+#define	__FSFILCNT_T_TYPE	__UQUAD_TYPE
+#define	__FSFILCNT64_T_TYPE	__FSFILCNT_T_TYPE
+#define	__FSWORD_T_TYPE		__SWORD_TYPE
+#define	__ID_T_TYPE		__U32_TYPE
+#define __CLOCK_T_TYPE		__SQUAD_TYPE
+#define __TIME_T_TYPE		__SQUAD_TYPE
+#define __USECONDS_T_TYPE	__U32_TYPE
+#define __SUSECONDS_T_TYPE	__S32_TYPE
+#define __DADDR_T_TYPE		__S32_TYPE
+#define __KEY_T_TYPE		__S32_TYPE
+#define __CLOCKID_T_TYPE	__S32_TYPE
+#define __TIMER_T_TYPE		void *
+#define __BLKSIZE_T_TYPE	__SLONGWORD_TYPE
+#define __FSID_T_TYPE		struct { int __val[2]; }
+#define __SSIZE_T_TYPE		__SWORD_TYPE
+#define __SYSCALL_SLONG_TYPE	__SLONGWORD_TYPE
+#define __SYSCALL_ULONG_TYPE	__ULONGWORD_TYPE
+
+/* All our foo64_t types match their foo_t counterparts.  */
+#define __OFF_T_MATCHES_OFF64_T	1
+#define __INO_T_MATCHES_INO64_T	1
+
+/* Number of descriptors that can fit in an `fd_set'.  */
+#define	__FD_SETSIZE		1024
+
+
+#endif /* bits/typesizes.h */
diff --git a/sysdeps/nacl/brk.c b/sysdeps/nacl/brk.c
new file mode 100644
index 0000000000..bc103de00c
--- /dev/null
+++ b/sysdeps/nacl/brk.c
@@ -0,0 +1,93 @@
+/* brk -- Adjust the "break" at the end of initial data.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <libc-internal.h>
+#include <stdint.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+/* sbrk.c expects this.  */
+void *__curbrk;
+
+static uintptr_t
+page_above (void *addr)
+{
+  return ALIGN_UP ((uintptr_t) addr, EXEC_PAGESIZE);
+}
+
+/* Set the end of the process's data space to ADDR.
+   Return 0 if successful, -1 if not.  */
+int
+__brk (void *addr)
+{
+  /* The NaCl sysbrk call is deprecated, so we do not use it here.  Other
+     libc code expects that __sbrk can be used at least a little bit, so
+     rather than a plain stub we have a minimal __brk implementation here.
+     It just uses mmap/munmap to grow or shrink the break area, punting as
+     soon as mmap fails to use the same contiguous area.  */
+
+  if (__glibc_unlikely (__curbrk == NULL))
+    {
+      /* This is the first call.  We must initialize the record
+         of the current position.  It starts out at the end of the
+         main program's data segment.  */
+
+      /* XXX dynamic case??? */
+      extern char _end[];
+      __curbrk = _end;
+    }
+
+  if (__glibc_unlikely (addr == NULL))
+    /* This is a call just to ensure that __curbrk is set up.  */
+    return 0;
+
+  uintptr_t old_limit = page_above (__curbrk);
+  uintptr_t new_limit = page_above (addr);
+
+  if (old_limit > new_limit)
+    {
+      /* We're shrinking the old heap enough to release some pages.  */
+      if (__munmap ((void *) new_limit, old_limit - new_limit) != 0)
+	return -1;
+    }
+  else if (old_limit < new_limit)
+    {
+      /* We're growing the old heap enough to need some more pages.
+	 See if they are available.  */
+      void *new_space = __mmap ((void *) old_limit, new_limit - old_limit,
+				PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
+      if (new_space != (void *) old_limit)
+	{
+          if (new_space != MAP_FAILED)
+            {
+              /* mmap chose some different place for the pages
+                 because the contiguous area was not available.
+                 Oh well.  We can't use that.  */
+              __munmap (new_space, new_limit - old_limit);
+              __set_errno (ENOMEM);
+            }
+	  return -1;
+	}
+    }
+
+  __curbrk = addr;
+  return 0;
+}
+weak_alias (__brk, brk)
diff --git a/sysdeps/nacl/chdir.c b/sysdeps/nacl/chdir.c
new file mode 100644
index 0000000000..e194ae95d1
--- /dev/null
+++ b/sysdeps/nacl/chdir.c
@@ -0,0 +1,28 @@
+/* Change current working directory.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Change the current directory to PATH.  */
+int
+__chdir (const char *path)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.chdir (path), 0);
+}
+weak_alias (__chdir, chdir)
diff --git a/sysdeps/nacl/check_fds.c b/sysdeps/nacl/check_fds.c
new file mode 100644
index 0000000000..a6bd8d8a5b
--- /dev/null
+++ b/sysdeps/nacl/check_fds.c
@@ -0,0 +1,23 @@
+/* Check inherited file descriptors for sanity at startup.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Nothing to do here.  */
+void
+__libc_check_standard_fds (void)
+{
+}
diff --git a/sysdeps/nacl/chmod.c b/sysdeps/nacl/chmod.c
new file mode 100644
index 0000000000..9a8ba097b5
--- /dev/null
+++ b/sysdeps/nacl/chmod.c
@@ -0,0 +1,28 @@
+/* Change a file's permissions.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Change the protections of FILE to MODE.  */
+int
+__chmod (const char *file, mode_t mode)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.chmod (file, mode), 0);
+}
+weak_alias (__chmod, chmod)
diff --git a/sysdeps/nacl/clock.c b/sysdeps/nacl/clock.c
new file mode 100644
index 0000000000..e3bf897c00
--- /dev/null
+++ b/sysdeps/nacl/clock.c
@@ -0,0 +1,29 @@
+/* Return the time used by the program so far.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <time.h>
+#include <nacl-interfaces.h>
+
+
+/* Return the time used by the program so far (user time + system time).  */
+clock_t
+clock (void)
+{
+  nacl_abi_clock_t result;
+  return NACL_CALL (__nacl_irt_basic.clock (&result), result);
+}
diff --git a/sysdeps/nacl/clock_getres.c b/sysdeps/nacl/clock_getres.c
new file mode 100644
index 0000000000..46052065e1
--- /dev/null
+++ b/sysdeps/nacl/clock_getres.c
@@ -0,0 +1,28 @@
+/* Get the resolution of a clock.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <time.h>
+#include <nacl-interfaces.h>
+
+/* Get resolution of clock.  */
+int
+__clock_getres (clockid_t clock_id, struct timespec *res)
+{
+  return NACL_CALL (__nacl_irt_clock.clock_getres (clock_id, res), 0);
+}
+weak_alias (__clock_getres, clock_getres)
diff --git a/sysdeps/nacl/clock_gettime.c b/sysdeps/nacl/clock_gettime.c
new file mode 100644
index 0000000000..8103ae3e4d
--- /dev/null
+++ b/sysdeps/nacl/clock_gettime.c
@@ -0,0 +1,29 @@
+/* Get the current value of a clock.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <time.h>
+#include <nacl-interfaces.h>
+
+/* Get current value of CLOCK and store it in TP.  */
+int
+__clock_gettime (clockid_t clock_id, struct timespec *tp)
+{
+  return NACL_CALL (__nacl_irt_clock.clock_gettime (clock_id, tp), 0);
+}
+libc_hidden_def (__clock_gettime)
+weak_alias (__clock_gettime, clock_gettime)
diff --git a/sysdeps/nacl/close.c b/sysdeps/nacl/close.c
new file mode 100644
index 0000000000..9f550f9964
--- /dev/null
+++ b/sysdeps/nacl/close.c
@@ -0,0 +1,31 @@
+/* Close a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+
+/* Close the file descriptor FD.  */
+int
+__close (int fd)
+{
+  return NACL_CALL (__nacl_irt_fdio.close (fd), 0);
+}
+libc_hidden_def (__close)
+strong_alias (__close, __libc_close)
+weak_alias (__close, close)
diff --git a/sysdeps/nacl/configure b/sysdeps/nacl/configure
new file mode 100644
index 0000000000..6bc753be03
--- /dev/null
+++ b/sysdeps/nacl/configure
@@ -0,0 +1,18 @@
+# This file is generated from configure.ac by Autoconf.  DO NOT EDIT!
+ # Local configure fragment for sysdeps/nacl.
+
+nacl_probe_file=native_client/src/trusted/service_runtime/include/sys/errno.h
+
+# sysheaders is set by the --with-headers=... option to configure.
+# For NaCl, we require that the option be given and point to the
+# native_client/.. source tree directory.
+test -n "$sysheaders" || {
+  as_fn_error $? "must supply --with-headers=DIR with native_client source tree" "$LINENO" 5
+}
+test -r "$sysheaders/$nacl_probe_file" || {
+  as_fn_error $? "$sysheaders does not appear to be a native_client source tree" "$LINENO" 5
+}
+
+# nscd is extremely useless in the NaCl context.
+build_nscd=no
+use_nscd=no
diff --git a/sysdeps/nacl/configure.ac b/sysdeps/nacl/configure.ac
new file mode 100644
index 0000000000..2c6f29fe1b
--- /dev/null
+++ b/sysdeps/nacl/configure.ac
@@ -0,0 +1,18 @@
+GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
+# Local configure fragment for sysdeps/nacl.
+
+nacl_probe_file=native_client/src/trusted/service_runtime/include/sys/errno.h
+
+# sysheaders is set by the --with-headers=... option to configure.
+# For NaCl, we require that the option be given and point to the
+# native_client/.. source tree directory.
+test -n "$sysheaders" || {
+  AC_MSG_ERROR([must supply --with-headers=DIR with native_client source tree])
+}
+test -r "$sysheaders/$nacl_probe_file" || {
+  AC_MSG_ERROR([$sysheaders does not appear to be a native_client source tree])
+}
+
+# nscd is extremely useless in the NaCl context.
+build_nscd=no
+use_nscd=no
diff --git a/sysdeps/nacl/createthread.c b/sysdeps/nacl/createthread.c
new file mode 100644
index 0000000000..9df4eaee74
--- /dev/null
+++ b/sysdeps/nacl/createthread.c
@@ -0,0 +1,46 @@
+/* Low-level thread creation for NPTL.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <nacl-interfaces.h>
+
+/* See the comments in pthread_create.c for the requirements for these
+   two macros and the create_thread function.  */
+
+#define START_THREAD_DEFN \
+  static void __attribute__ ((noreturn)) start_thread (void)
+#define START_THREAD_SELF THREAD_SELF
+
+/* pthread_create.c defines this using START_THREAD_DEFN
+   We need a forward declaration here so we can take its address.  */
+static void start_thread (void) __attribute__ ((noreturn));
+
+static int
+create_thread (struct pthread *pd, const struct pthread_attr *attr,
+	       bool stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+{
+  pd->stopped_start = stopped_start;
+  if (__glibc_unlikely (stopped_start))
+    /* We make sure the thread does not run far by forcing it to get a
+       lock.  We lock it here too so that the new thread cannot continue
+       until we tell it to.  */
+    lll_lock (pd->lock, LLL_PRIVATE);
+
+  TLS_DEFINE_INIT_TP (tp, pd);
+
+  return __nacl_irt_thread.thread_create (&start_thread, stackaddr, tp);
+}
diff --git a/sysdeps/nacl/dl-map-segments.h b/sysdeps/nacl/dl-map-segments.h
new file mode 100644
index 0000000000..f305da304a
--- /dev/null
+++ b/sysdeps/nacl/dl-map-segments.h
@@ -0,0 +1,238 @@
+/* Map in a shared object's segments.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <dl-load.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <libc-internal.h>
+
+
+/* This is basically pread, but with iteration after short reads.  */
+static bool
+read_in_data (int fd, void *data, size_t len, off_t pos)
+{
+  if (__glibc_unlikely (__lseek (fd, pos, SEEK_SET) == (off_t) -1))
+    return true;
+  while (len > 0)
+    {
+      ssize_t n = __read (fd, data, len);
+      if (__glibc_unlikely (n < 0))
+	return true;
+      if (__glibc_unlikely (n == 0))
+	{
+	  errno = EFTYPE;
+	  return true;
+	}
+      data += n;
+      len -= n;
+    }
+  return false;
+}
+
+static const char *
+_dl_map_segments (struct link_map *l, int fd,
+		  const ElfW(Ehdr) *header, int type,
+		  const struct loadcmd loadcmds[], size_t nloadcmds,
+		  const size_t maplength, bool has_holes,
+		  struct link_map *loader)
+{
+  if (__builtin_expect (type, ET_DYN) == ET_DYN)
+    {
+      /* This is a position-independent shared object.  Let the system
+	 choose where to place it.
+
+	 As a refinement, sometimes we have an address that we would
+	 prefer to map such objects at; but this is only a preference,
+	 the OS can do whatever it likes. */
+      ElfW(Addr) mappref
+	= (ELF_PREFERRED_ADDRESS (loader, maplength,
+				  loadcmds[0].mapstart & GLRO(dl_use_load_bias))
+	   - MAP_BASE_ADDR (l));
+
+      uintptr_t mapstart;
+      if (__glibc_likely (loadcmds[0].prot & PROT_EXEC))
+	{
+	  /* When there is a code segment, we must use the
+	     allocate_code_data interface to choose a location.  */
+
+	  uintptr_t code_size = loadcmds[0].allocend - loadcmds[0].mapstart;
+	  uintptr_t data_offset;
+	  size_t data_size;
+
+	  if (__glibc_likely (nloadcmds > 1))
+	    {
+	      data_offset = loadcmds[1].mapstart - loadcmds[0].mapstart;
+	      data_size = ALIGN_UP (maplength - data_offset,
+				    GLRO(dl_pagesize));
+	    }
+	  else
+	    {
+	      data_offset = 0;
+	      data_size = 0;
+	    }
+
+	  int error = __nacl_irt_code_data_alloc.allocate_code_data
+	    (mappref, code_size, data_offset, data_size, &mapstart);
+	  if (__glibc_unlikely (error))
+	    {
+	      errno = error;
+	      return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+	    }
+	}
+      else
+	{
+	  /* With no code pages involved, plain mmap works fine.  */
+	  void *mapped = __mmap ((void *) mappref, maplength,
+				 PROT_NONE, MAP_ANON, -1, 0);
+	  if (__glibc_unlikely (mapped == MAP_FAILED))
+	    return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+	  mapstart = (uintptr_t) mapped;
+	}
+
+      l->l_addr = mapstart - loadcmds[0].mapstart;
+    }
+
+  /* Remember which part of the address space this object uses.  */
+  l->l_map_start = loadcmds[0].mapstart + l->l_addr;
+  l->l_map_end = l->l_map_start + maplength;
+  l->l_contiguous = !has_holes;
+
+  /* Now actually map (or read) in each segment.  */
+  for (const struct loadcmd *c = loadcmds; c < &loadcmds[nloadcmds]; ++c)
+    if (__glibc_likely (c->mapend > c->mapstart))
+      {
+	/* Unlike POSIX mmap, NaCl's mmap does not reliably handle COW
+	   faults in the remainder of the final partial page.  So to get
+	   the expected behavior for the unaligned boundary between data
+	   and bss, it's necessary to allocate the final partial page of
+	   data as anonymous memory rather than mapping it from the file.  */
+
+	size_t maplen = c->mapend - c->mapstart;
+	if (c->mapend > c->dataend && c->allocend > c->dataend)
+	  maplen = (c->dataend & -GLRO(dl_pagesize)) - c->mapstart;
+
+	/* Map the segment contents from the file.  */
+	if (__glibc_unlikely (__mmap ((void *) (l->l_addr + c->mapstart),
+				      maplen, c->prot,
+				      MAP_FIXED|MAP_COPY|MAP_FILE,
+				      fd, c->mapoff)
+			      == MAP_FAILED))
+	  {
+	    switch (errno)
+	      {
+	      case EINVAL:
+	      case ENOTSUP:
+	      case ENOSYS:
+		break;
+	      default:
+		return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+	      }
+
+	    /* No mmap support for this file.  */
+	    if (c->prot & PROT_EXEC)
+	      {
+		/* Read the data into a temporary buffer.  */
+		const size_t len = c->mapend - c->mapstart;
+		void *data = __mmap (NULL, len, PROT_READ | PROT_WRITE,
+				     MAP_ANON|MAP_PRIVATE, -1, 0);
+		if (__glibc_unlikely (data == MAP_FAILED))
+		  return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
+		if (read_in_data (fd, data, len, c->mapoff))
+		  return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+		/* Now validate and install the code.  */
+		int error = __nacl_irt_dyncode.dyncode_create
+		  ((void *) (l->l_addr + c->mapstart), data, len);
+		__munmap (data, len);
+		if (__glibc_unlikely (error))
+		  {
+		    errno = error;
+		    return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+		  }
+	      }
+	    else
+	      {
+		/* Allocate the pages.  */
+		if (__mmap ((void *) (l->l_addr + c->mapstart),
+			    c->mapend - c->mapstart, c->prot | PROT_WRITE,
+			    MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
+		    == MAP_FAILED)
+		  return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
+		/* Now read in the data.  */
+		if (read_in_data (fd, (void *) (l->l_addr + c->mapstart),
+				  c->dataend - c->mapstart, c->mapoff))
+		  return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+		/* Now that we've filled the pages, reset the page
+		   protections to what they should be.  */
+		if (!(c->prot & PROT_WRITE)
+		    && __mprotect ((void *) (l->l_addr + c->mapstart),
+				   c->mapend - c->mapstart, c->prot) < 0)
+		  return DL_MAP_SEGMENTS_ERROR_MPROTECT;
+	      }
+	  }
+	else if (c->allocend > c->dataend)
+	  {
+	    /* Extra zero pages should appear at the end of this segment,
+	       after the data mapped from the file.   */
+
+	    uintptr_t allocend = c->mapend;
+	    if (c->mapend > c->dataend)
+	      {
+		/* The final data page was partial.  So we didn't map it in.
+		   Instead, we must allocate an anonymous page to fill.  */
+		if (c->prot & PROT_WRITE)
+		  /* Do the whole allocation right here.  */
+		  allocend = c->allocend;
+		if (__mmap ((void *) (l->l_addr + c->mapstart + maplen),
+			    allocend - (c->mapstart + maplen), c->prot,
+			    MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
+		    == MAP_FAILED)
+		  return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
+		if (read_in_data (fd,
+				  (void *) (l->l_addr + c->mapstart + maplen),
+				  c->dataend & (GLRO(dl_pagesize) - 1),
+				  c->mapoff + maplen))
+		  return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
+		/* Now that we've filled the page, reset its
+		   protections to what they should be.  */
+		if (!(c->prot & PROT_WRITE)
+		    && __mprotect ((void *) (l->l_addr + c->mapstart + maplen),
+				   c->mapend - (c->mapstart + maplen),
+				   c->prot) < 0)
+		  return DL_MAP_SEGMENTS_ERROR_MPROTECT;
+	      }
+
+	    /* Now allocate the pure zero-fill pages.  */
+	    if (allocend < c->allocend
+		&& (__mmap ((void *) (l->l_addr + c->mapstart + allocend),
+			   c->allocend - (c->mapstart + allocend), c->prot,
+			   MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
+		    == MAP_FAILED))
+	      return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
+	  }
+
+	_dl_postprocess_loadcmd (l, header, c);
+      }
+
+  /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
+     fixed.  */
+  ELF_FIXED_ADDRESS (loader, c->mapstart);
+
+  return NULL;
+}
diff --git a/sysdeps/nacl/dl-osinfo.h b/sysdeps/nacl/dl-osinfo.h
new file mode 100644
index 0000000000..ee74d9dd42
--- /dev/null
+++ b/sysdeps/nacl/dl-osinfo.h
@@ -0,0 +1,34 @@
+/* DL_SYSDEP_OSCHECK macro for NaCl.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _DL_OSINFO_H
+#define _DL_OSINFO_H  1
+
+#include <sysdeps/generic/dl-osinfo.h>
+
+#include "nacl-interfaces.h"
+
+#ifndef SHARED
+/* This doesn't really have anything to do with the purpose for
+   which this macro is used in Linux configurations.  But it is
+   called at the right place in __libc_start_main.  */
+# define DL_SYSDEP_OSCHECK(fatal)	__nacl_initialize_interfaces ()
+#endif
+
+
+#endif /* dl-osinfo.h */
diff --git a/sysdeps/nacl/dl-sysdep.c b/sysdeps/nacl/dl-sysdep.c
new file mode 100644
index 0000000000..3e902c2cae
--- /dev/null
+++ b/sysdeps/nacl/dl-sysdep.c
@@ -0,0 +1,89 @@
+/* Operating system support for run-time dynamic linker.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifdef SHARED
+
+# include <assert.h>
+# include <ldsodefs.h>
+# include <stdint.h>
+# include <nacl-interfaces.h>
+
+/* NaCl's elf32.h is incompatible with the real <elf.h>.  */
+# define NATIVE_CLIENT_SRC_INCLUDE_ELF32_H_
+# include <native_client/src/untrusted/nacl/nacl_startup.h>
+
+/* The RTLD_START code sets up the pointer that gets to these
+   macros as COOKIE to point to two words:
+   [0] the argument to the entry point from the system (see nacl_startup.h)
+   [1] the stack base
+*/
+
+# define DL_FIND_ARG_COMPONENTS(cookie, argc, argv, envp, auxp)	\
+  do {								\
+    uint32_t *_info = ((void **) (cookie))[0];			\
+    (argc) = nacl_startup_argc (_info);				\
+    (argv) = nacl_startup_argv (_info);				\
+    (envp) = nacl_startup_envp (_info);				\
+    (auxp) = nacl_startup_auxv (_info);				\
+  } while (0)
+
+# define DL_STACK_END(cookie)	(((void **) (cookie))[1])
+
+/* This is called from the entry point (_start), defined by the RTLD_START
+   macro in the machine-specific dl-machine.h file.  At this point, dynamic
+   linking has been completed and the first argument is the application's
+   entry point.  */
+attribute_hidden internal_function __attribute__ ((noreturn))
+void
+_dl_start_user (void (*user_entry) (uint32_t info[]), uint32_t info[])
+{
+  if (_dl_skip_args > 0)
+    {
+      /* There are some arguments that the user program should not see.
+	 Just slide up the INFO pointer so its NACL_STARTUP_ARGV points
+	 to what should now be argv[0], and copy back the earlier fields.  */
+      assert (nacl_startup_argc (info) >= _dl_skip_args);
+      assert (NACL_STARTUP_ARGV == 3);
+      uint32_t envc = info[NACL_STARTUP_ENVC];
+      uint32_t argc = info[NACL_STARTUP_ARGC];
+      info += _dl_skip_args;
+      info[NACL_STARTUP_ENVC] = envc;
+      info[NACL_STARTUP_ARGC] = argc - _dl_skip_args;
+    }
+
+  /* Pass our finalizer function to the user.  */
+  info[NACL_STARTUP_FINI] = (uintptr_t) &_dl_fini;
+
+  /* Run initializers.  */
+  _dl_init (GL(dl_ns)[0]._ns_loaded,
+	    nacl_startup_argc (info),
+	    nacl_startup_argv (info),
+	    nacl_startup_envp (info));
+
+  /* Call the user's entry point.  This should never return.  */
+  (*user_entry) (info);
+
+  /* Fail clearly just in case it did return.  */
+  __builtin_trap ();
+}
+
+# define DL_SYSDEP_INIT	__nacl_initialize_interfaces ()
+
+#endif  /* SHARED */
+
+#include <elf/dl-sysdep.c>
diff --git a/sysdeps/nacl/dl-sysdep.h b/sysdeps/nacl/dl-sysdep.h
new file mode 100644
index 0000000000..ade4213578
--- /dev/null
+++ b/sysdeps/nacl/dl-sysdep.h
@@ -0,0 +1,30 @@
+/* System-specific settings for dynamic linker code.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* No multiple inclusion protection needed here because it's just macros.
+   We don't want to use _DL_SYSDEP_H in case we are #include_next'd.  */
+
+#include_next <dl-sysdep.h>
+
+/* We use AT_SYSINFO for a different purpose than Linux does,
+   but we too want to store its value.  */
+#define NEED_DL_SYSINFO         1
+#define DL_SYSINFO_DEFAULT      0
+
+/* sysdeps/arm/dl-sysdep.h defines this but it does not apply to NaCl.  */
+#undef  DL_ARGV_NOT_RELRO
diff --git a/sysdeps/nacl/dl-unmap-segments.h b/sysdeps/nacl/dl-unmap-segments.h
new file mode 100644
index 0000000000..02851e7dc3
--- /dev/null
+++ b/sysdeps/nacl/dl-unmap-segments.h
@@ -0,0 +1,65 @@
+/* Unmap a shared object's segments.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _DL_UNMAP_SEGMENTS_H
+#define _DL_UNMAP_SEGMENTS_H    1
+
+#include <link.h>
+#include <sys/mman.h>
+
+/* There is always a big gap between the executable segment and the data
+   segments.  Other code segments and data pages lie in there.  So we must
+   unmap each segment individually (except for a codeless module).  */
+
+static void __always_inline
+_dl_unmap_segments (struct link_map *l)
+{
+  if (l->l_contiguous)
+    /* Simple case.  */
+    __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);
+  else
+    {
+      /* Normally l_phdr points into the RODATA segment, which we will
+         unmap in one iteration of the loop.  So we cannot use it directly
+         throughout.  */
+
+      struct { ElfW(Addr) start, end; } segments[l->l_phnum], *seg = segments;
+
+      for (const ElfW(Phdr) *ph = l->l_phdr; ph < &l->l_phdr[l->l_phnum]; ++ph)
+        if (ph->p_type == PT_LOAD)
+          {
+            seg->start = (l->l_addr + ph->p_vaddr) & -GLRO(dl_pagesize);
+            seg->end = (l->l_addr + ph->p_vaddr + ph->p_memsz
+                        + GLRO(dl_pagesize) - 1) & -GLRO(dl_pagesize);
+            if (seg > segments && seg[-1].end == seg->start)
+              /* Coalesce two adjacent segments into one munmap call.  */
+              seg[-1].end = seg->end;
+            else
+              ++seg;
+          }
+
+      do
+        {
+          --seg;
+          __munmap ((void *) seg->start, seg->end - seg->start);
+        }
+      while (seg > segments);
+    }
+}
+
+#endif  /* dl-unmap-segments.h */
diff --git a/sysdeps/nacl/dl-writev.h b/sysdeps/nacl/dl-writev.h
new file mode 100644
index 0000000000..e61d9d14f9
--- /dev/null
+++ b/sysdeps/nacl/dl-writev.h
@@ -0,0 +1,45 @@
+/* Message-writing for the dynamic linker.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/uio.h>
+#include <nacl-interfaces.h>
+
+/* This is used from only one place: dl-misc.c:_dl_debug_vdprintf.
+   Hence it's in a header with the expectation it will be inlined.
+
+   This is writev, but with a constraint added and others loosened:
+
+   1. Under RTLD_PRIVATE_ERRNO, it must not clobber the private errno
+      when another thread holds the dl_load_lock.
+   2. It is not obliged to detect and report errors at all.
+   3. It's not really obliged to deliver a single atomic write
+      (though it may be preferable).  */
+
+static inline void
+_dl_writev (int fd, const struct iovec *iov, size_t niov)
+{
+  for (size_t i = 0; i < niov; ++i)
+    {
+      size_t wrote;
+      if (__nacl_irt_fdio.write (fd, iov[i].iov_base, iov[i].iov_len,
+                                 &wrote) != 0
+          || wrote != iov[i].iov_len)
+        /* The write failed, so don't bother trying any more.  */
+        break;
+    }
+}
diff --git a/sysdeps/nacl/dup.c b/sysdeps/nacl/dup.c
new file mode 100644
index 0000000000..1f66c521c7
--- /dev/null
+++ b/sysdeps/nacl/dup.c
@@ -0,0 +1,30 @@
+/* Duplicate a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+
+/* Duplicate FD, returning a new file descriptor open on the same file.  */
+int
+__dup (int fd)
+{
+  int result;
+  return NACL_CALL (__nacl_irt_fdio.dup (fd, &result), result);
+}
+weak_alias (__dup, dup)
diff --git a/sysdeps/nacl/dup2.c b/sysdeps/nacl/dup2.c
new file mode 100644
index 0000000000..948a10892f
--- /dev/null
+++ b/sysdeps/nacl/dup2.c
@@ -0,0 +1,31 @@
+/* Duplicate a file descriptor to a chosen number.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+
+/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
+   open the same file as FD is.  Return FD2 or -1.  */
+int
+__dup2 (int fd, int fd2)
+{
+  return NACL_CALL (__nacl_irt_fdio.dup2 (fd, fd2), fd2);
+}
+libc_hidden_def (__dup2)
+weak_alias (__dup2, dup2)
diff --git a/sysdeps/nacl/entry.h b/sysdeps/nacl/entry.h
new file mode 100644
index 0000000000..e9dc190e34
--- /dev/null
+++ b/sysdeps/nacl/entry.h
@@ -0,0 +1,6 @@
+#ifndef __ASSEMBLY__
+# include <stdint.h>
+extern void _start (uint32_t info[]) attribute_hidden;
+#endif
+
+#define ENTRY_POINT _start
diff --git a/sysdeps/nacl/errnos.awk b/sysdeps/nacl/errnos.awk
new file mode 100644
index 0000000000..65fa19bd06
--- /dev/null
+++ b/sysdeps/nacl/errnos.awk
@@ -0,0 +1,87 @@
+# Script to produce bits/errno.h for NaCl.
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+BEGIN { maxerrno = 0 }
+
+$1 == "#define" && $2 ~ /NACL_ABI_E[A-Z0-9_]+/ && $3 ~ /[0-9]+/ {
+  ename = $2;
+  sub(/NACL_ABI_/, "", ename);
+  errno = $3 + 0;
+  if (errno > maxerrno) maxerrno = errno;
+  errnos[errno] = ename;
+  errnos_by_name[ename] = errno;
+  if ($4 == "/*" && !(ename in errno_text)) {
+    etext = $5;
+    for (i = 6; i <= NF && $i != "*/"; ++i)
+      etext = etext " " $i;
+    errno_text[ename] = etext;
+  }
+  next;
+}
+
+$1 == "@comment" && $2 == "errno.h" { errnoh=1; next }
+errnoh == 1 && $1 == "@comment" {
+  ++errnoh;
+  etext = $3;
+  for (i = 4; i <= NF; ++i)
+    etext = etext " " $i;
+  next;
+}
+errnoh == 2 && $1 == "@deftypevr" && $2 == "Macro" && $3 == "int" {
+  ename = $4;
+  errno_text[ename] = etext;
+  next;
+}
+
+function define_errno(errno, ename) {
+  etext = errno_text[ename];
+  if (length(ename) < 8) ename = ename "\t";
+  printf "#define\t%s\t%d\t/* %s */\n", ename, errno, etext;
+}
+
+END {
+  print "\
+/* This file generated by errnos.awk.  */\n\
+\n\
+#if !defined __Emath_defined && (defined _ERRNO_H || defined __need_Emath)\n\
+#undef	__need_Emath\n\
+#define	__Emath_defined	1";
+  emath["EDOM"] = emath["EILSEQ"] = emath["ERANGE"] = 1;
+  for (ename in emath) {
+    errno = errnos_by_name[ename];
+    define_errno(errno, ename);
+    delete errnos[errno];
+  }
+  print "\
+#endif\n\
+\n\
+#ifdef _ERRNO_H\n";
+
+  for (i = 1; i <= maxerrno; ++i)
+    if (i in errnos) define_errno(i, errnos[i]);
+
+  print "\n\
+#define	EWOULDBLOCK	EAGAIN\n\
+#define	ENOTSUP		EOPNOTSUPP\n\
+\n\
+extern __thread int errno __attribute__ ((__tls_model__ (\"initial-exec\")));\n\
+#define errno errno\n\
+\n\
+#endif";
+}
diff --git a/sysdeps/nacl/euidaccess.c b/sysdeps/nacl/euidaccess.c
new file mode 100644
index 0000000000..036e736001
--- /dev/null
+++ b/sysdeps/nacl/euidaccess.c
@@ -0,0 +1,27 @@
+/* Check file access permission.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+
+/* Test for access to FILE.  */
+int
+euidaccess (const char *file, int type)
+{
+  /* No NaCl process will ever be set-ID, so access and euidaccess are one.  */
+  return __access (file, type);
+}
diff --git a/sysdeps/nacl/exit-thread.h b/sysdeps/nacl/exit-thread.h
new file mode 100644
index 0000000000..a08a5b1d5c
--- /dev/null
+++ b/sysdeps/nacl/exit-thread.h
@@ -0,0 +1,35 @@
+/* Call to terminate the current thread.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stddef.h>
+#include <nacl-interfaces.h>
+
+/* This causes the current thread to exit, without affecting other
+   threads in the process if there are any.  If there are no other
+   threads left, then this has the effect of _exit (0).  */
+
+static inline void __attribute__ ((noreturn, always_inline, unused))
+__exit_thread (void)
+{
+  __nacl_irt_thread.thread_exit (NULL);
+
+  /* That never returns unless something is severely and unrecoverably wrong.
+     If it ever does, try to make sure we crash.  */
+  while (1)
+    __builtin_trap ();
+}
diff --git a/sysdeps/nacl/fchdir.c b/sysdeps/nacl/fchdir.c
new file mode 100644
index 0000000000..4295bc2c6d
--- /dev/null
+++ b/sysdeps/nacl/fchdir.c
@@ -0,0 +1,28 @@
+/* Change working directory given a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Change the current directory to FD.  */
+int
+__fchdir (int fd)
+{
+  return NACL_CALL (__nacl_irt_dev_fdio.fchdir (fd), 0);
+}
+weak_alias (__fchdir, fchdir)
diff --git a/sysdeps/nacl/fchmod.c b/sysdeps/nacl/fchmod.c
new file mode 100644
index 0000000000..35d6939cb2
--- /dev/null
+++ b/sysdeps/nacl/fchmod.c
@@ -0,0 +1,28 @@
+/* Change a file's permissions given a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Change the permissions of the file referenced by FD to MODE.  */
+int
+__fchmod (int fd, mode_t mode)
+{
+  return NACL_CALL (__nacl_irt_dev_fdio.fchmod (fd, mode), 0);
+}
+weak_alias (__fchmod, fchmod)
diff --git a/sysdeps/nacl/fdatasync.c b/sysdeps/nacl/fdatasync.c
new file mode 100644
index 0000000000..cd7a55ff41
--- /dev/null
+++ b/sysdeps/nacl/fdatasync.c
@@ -0,0 +1,28 @@
+/* Make all changes done to file data actually appear on disk.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Synchronize at least the data part of a file with the underlying
+   media.  */
+int
+fdatasync (int fd)
+{
+  return NACL_CALL (__nacl_irt_dev_fdio.fdatasync (fd), 0);
+}
diff --git a/sysdeps/nacl/fork.c b/sysdeps/nacl/fork.c
new file mode 100644
index 0000000000..9f06944aa7
--- /dev/null
+++ b/sysdeps/nacl/fork.c
@@ -0,0 +1,3 @@
+/* Get the stub, bypassing the "generic" NPTL code.  */
+#include <posix/fork.c>
+strong_alias (__fork, __libc_fork)
diff --git a/sysdeps/nacl/fsync.c b/sysdeps/nacl/fsync.c
new file mode 100644
index 0000000000..6f6622b7db
--- /dev/null
+++ b/sysdeps/nacl/fsync.c
@@ -0,0 +1,27 @@
+/* Make all changes done to FD actually appear on disk.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Make all changes done to FD actually appear on disk.  */
+int
+fsync (int fd)
+{
+  return NACL_CALL (__nacl_irt_dev_fdio.fsync (fd), 0);
+}
diff --git a/sysdeps/nacl/ftruncate.c b/sysdeps/nacl/ftruncate.c
new file mode 100644
index 0000000000..1235f0d804
--- /dev/null
+++ b/sysdeps/nacl/ftruncate.c
@@ -0,0 +1,32 @@
+/* Truncate a file.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Truncate the file referenced by FD to LENGTH bytes.  */
+int
+__ftruncate (int fd, off_t length)
+{
+  return NACL_CALL (__nacl_irt_dev_fdio.ftruncate (fd, length), 0);
+}
+weak_alias (__ftruncate, ftruncate)
+
+/* ftruncate64 is the same as ftruncate.  */
+strong_alias (__ftruncate, __ftruncate64)
+weak_alias (__ftruncate64, ftruncate64)
diff --git a/sysdeps/nacl/ftruncate64.c b/sysdeps/nacl/ftruncate64.c
new file mode 100644
index 0000000000..e40129af66
--- /dev/null
+++ b/sysdeps/nacl/ftruncate64.c
@@ -0,0 +1 @@
+/* ftruncate64 is the same as ftruncate.  */
diff --git a/sysdeps/nacl/fxstat.c b/sysdeps/nacl/fxstat.c
new file mode 100644
index 0000000000..d9f3d20afa
--- /dev/null
+++ b/sysdeps/nacl/fxstat.c
@@ -0,0 +1,45 @@
+/* Get stat information from a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Avoid the declaration so the compiler doesn't complain about the alias
+   with a different type signature.  It doesn't know that 'struct stat'
+   and 'struct stat64' are ABI-compatible.  */
+#define __fxstat64 __fxstat64_avoid
+#include <sys/stat.h>
+#undef  __fxstat64
+
+#include <errno.h>
+#include <stddef.h>
+
+#include <xstatconv.h>
+
+#undef  fstat
+
+/* Get information about the file descriptor FD in BUF.  */
+int
+__fxstat (int vers, int fd, struct stat *buf)
+{
+  nacl_abi_stat_t abi_buf;
+  return NACL_CALL (__nacl_irt_fdio.fstat (fd, &abi_buf),
+                    __xstat_conv (vers, &abi_buf, buf));
+}
+hidden_def (__fxstat)
+weak_alias (__fxstat, _fxstat)
+
+strong_alias (__fxstat, __fxstat64)
+hidden_ver (__fxstat, __fxstat64)
diff --git a/sysdeps/nacl/fxstat64.c b/sysdeps/nacl/fxstat64.c
new file mode 100644
index 0000000000..72aae12fe9
--- /dev/null
+++ b/sysdeps/nacl/fxstat64.c
@@ -0,0 +1 @@
+/* fxstat.c defines __fxstat64 as an alias.  */
diff --git a/sysdeps/nacl/getcwd.c b/sysdeps/nacl/getcwd.c
new file mode 100644
index 0000000000..ba7e49a036
--- /dev/null
+++ b/sysdeps/nacl/getcwd.c
@@ -0,0 +1,56 @@
+/* Get current working directory.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <nacl-interfaces.h>
+
+/* Get the pathname of the current working directory,
+   and put it in SIZE bytes of BUF.  Returns NULL if the
+   directory couldn't be determined or SIZE was too small.
+   If successful, returns BUF.  In GNU, if BUF is NULL,
+   an array is allocated with `malloc'; the array is SIZE
+   bytes long, unless SIZE <= 0, in which case it is as
+   big as necessary.  */
+char *
+__getcwd (char *buf, size_t size)
+{
+  char *use_buf = buf;
+
+  if (buf == NULL)
+    {
+      if (size == 0)
+        size = PATH_MAX;
+      use_buf = malloc (size);
+      if (__glibc_unlikely (use_buf == NULL))
+        return NULL;
+    }
+
+  int error = __nacl_irt_dev_filename.getcwd (use_buf, size);
+  if (__glibc_unlikely (error))
+    {
+      if (use_buf != buf)
+        free (use_buf);
+      errno = error;
+      return NULL;
+    }
+
+  return use_buf;
+}
+weak_alias (__getcwd, getcwd)
diff --git a/sysdeps/nacl/getdents.c b/sysdeps/nacl/getdents.c
new file mode 100644
index 0000000000..e022b6bd5b
--- /dev/null
+++ b/sysdeps/nacl/getdents.c
@@ -0,0 +1,29 @@
+/* Read directory entries from a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <dirent.h>
+#include <nacl-interfaces.h>
+
+ssize_t
+internal_function
+__getdents (int fd, char *buf, size_t nbytes)
+{
+  size_t nread;
+  return NACL_CALL (__nacl_irt_fdio.getdents (fd, (void *) buf, nbytes, &nread),
+                    nread);
+}
diff --git a/sysdeps/nacl/getdents64.c b/sysdeps/nacl/getdents64.c
new file mode 100644
index 0000000000..730861899c
--- /dev/null
+++ b/sysdeps/nacl/getdents64.c
@@ -0,0 +1 @@
+/* We do not define a getdirentries or getdirentries64 entry point at all.  */
diff --git a/sysdeps/nacl/getdtsz.c b/sysdeps/nacl/getdtsz.c
new file mode 100644
index 0000000000..31c9978103
--- /dev/null
+++ b/sysdeps/nacl/getdtsz.c
@@ -0,0 +1,28 @@
+/* getdtablesize -- Return the limit on file descriptor values.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+
+/* Return the maximum number of file descriptors
+   the current process could possibly have.  */
+int
+__getdtablesize (void)
+{
+  /* There is no actual limit in NaCl, just memory.  */
+  return -1;
+}
diff --git a/sysdeps/nacl/getpagesize.c b/sysdeps/nacl/getpagesize.c
new file mode 100644
index 0000000000..0be1ccf072
--- /dev/null
+++ b/sysdeps/nacl/getpagesize.c
@@ -0,0 +1 @@
+#include <sysdeps/unix/getpagesize.c>
diff --git a/sysdeps/nacl/getpid.c b/sysdeps/nacl/getpid.c
new file mode 100644
index 0000000000..1b6d2d5d31
--- /dev/null
+++ b/sysdeps/nacl/getpid.c
@@ -0,0 +1,32 @@
+/* Get the process ID of the calling process.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Get the process ID of the calling process.  */
+pid_t
+__getpid (void)
+{
+  int pid;
+  return NACL_CALL (__nacl_irt_dev_getpid.getpid (&pid), pid);
+}
+libc_hidden_def (__getpid)
+weak_alias (__getpid, getpid)
+libc_hidden_weak (getpid)
diff --git a/sysdeps/nacl/getsysstats.c b/sysdeps/nacl/getsysstats.c
new file mode 100644
index 0000000000..97a2edb459
--- /dev/null
+++ b/sysdeps/nacl/getsysstats.c
@@ -0,0 +1,65 @@
+/* getsysstats - Determine various system internal values.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/sysinfo.h>
+#include <nacl-interfaces.h>
+
+#undef __native_client__
+#include "native_client/src/trusted/service_runtime/include/sys/unistd.h"
+
+
+int
+__get_nprocs_conf (void)
+{
+  int nprocs;
+  if (__nacl_irt_basic.sysconf (NACL_ABI__SC_NPROCESSORS_ONLN, &nprocs) != 0)
+    /* On failure (which should be impossible), just report one processor.  */
+    nprocs = 1;
+  return nprocs;
+}
+weak_alias (__get_nprocs_conf, get_nprocs_conf)
+
+int
+__get_nprocs (void)
+{
+  return __get_nprocs_conf ();
+}
+weak_alias (__get_nprocs, get_nprocs)
+
+
+long int
+__get_phys_pages (void)
+{
+  /* We have no general way to determine this value.  */
+  __set_errno (ENOSYS);
+  return -1;
+}
+weak_alias (__get_phys_pages, get_phys_pages)
+stub_warning (get_phys_pages)
+
+
+long int
+__get_avphys_pages (void)
+{
+  /* We have no general way to determine this value.  */
+  __set_errno (ENOSYS);
+  return -1;
+}
+weak_alias (__get_avphys_pages, get_avphys_pages)
+stub_warning (get_avphys_pages)
diff --git a/sysdeps/nacl/gettimeofday.c b/sysdeps/nacl/gettimeofday.c
new file mode 100644
index 0000000000..9fb8dab4fd
--- /dev/null
+++ b/sysdeps/nacl/gettimeofday.c
@@ -0,0 +1,40 @@
+/* Get the current wall clock time.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/time.h>
+#include <nacl-interfaces.h>
+
+
+/* Get the current time of day and timezone information,
+   putting it into *TV and *TZ.  If TZ is NULL, *TZ is not filled.
+   Returns 0 on success, -1 on errors.  */
+int
+__gettimeofday (struct timeval *tv, struct timezone *tz)
+{
+  if (__glibc_unlikely (tz != NULL))
+    {
+      tz->tz_minuteswest = 0;
+      tz->tz_dsttime = 0;
+    }
+
+  return NACL_CALL (__nacl_irt_basic.gettod (tv), 0);
+}
+libc_hidden_def (__gettimeofday)
+weak_alias (__gettimeofday, gettimeofday)
+libc_hidden_weak (gettimeofday)
diff --git a/sysdeps/nacl/glob.c b/sysdeps/nacl/glob.c
new file mode 100644
index 0000000000..36d62e807d
--- /dev/null
+++ b/sysdeps/nacl/glob.c
@@ -0,0 +1,26 @@
+/* Do glob searching.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>			/* Declares getlogin_r.  */
+
+/* We do not have getlogin_r in the library at all for NaCl.
+   Define it away so the glob code does not try to use it.  */
+#define getlogin_r(name, len)		(ENOSYS)
+
+/* Fetch the version that defines glob64 as an alias.  */
+#include <sysdeps/wordsize-64/glob.c>
diff --git a/sysdeps/nacl/glob64.c b/sysdeps/nacl/glob64.c
new file mode 100644
index 0000000000..adca2d4a49
--- /dev/null
+++ b/sysdeps/nacl/glob64.c
@@ -0,0 +1 @@
+#include <sysdeps/wordsize-64/glob64.c>
diff --git a/sysdeps/nacl/ifaddrs.c b/sysdeps/nacl/ifaddrs.c
new file mode 100644
index 0000000000..0e6485170b
--- /dev/null
+++ b/sysdeps/nacl/ifaddrs.c
@@ -0,0 +1,2 @@
+/* Bypass the sysdeps/gnu version to get the plain stub.  */
+#include <inet/ifaddrs.c>
diff --git a/sysdeps/nacl/init-first.c b/sysdeps/nacl/init-first.c
new file mode 100644
index 0000000000..5830c6fd69
--- /dev/null
+++ b/sysdeps/nacl/init-first.c
@@ -0,0 +1,27 @@
+/* Initialization code run first thing by the ELF startup code.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifdef SHARED
+
+# include <nacl-interfaces.h>
+
+# define VDSO_SETUP     __nacl_initialize_interfaces
+
+#endif
+
+#include <csu/init-first.c>
diff --git a/sysdeps/nacl/iofdopen.c b/sysdeps/nacl/iofdopen.c
new file mode 100644
index 0000000000..fd5271f4eb
--- /dev/null
+++ b/sysdeps/nacl/iofdopen.c
@@ -0,0 +1,26 @@
+/* Open a stream from a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fcntl.h>
+
+/* NaCl does not have a functioning fcntl, so don't use the stub and fail.  */
+#undef  F_GETFL
+#undef  F_SETFL
+#define __fcntl(...)    ???should not be called???
+
+#include <libio/iofdopen.c>
diff --git a/sysdeps/nacl/irt.sed b/sysdeps/nacl/irt.sed
new file mode 100644
index 0000000000..0abe17701e
--- /dev/null
+++ b/sysdeps/nacl/irt.sed
@@ -0,0 +1,12 @@
+# This sed script massages native_client/src/untrusted/irt/irt.h into
+# the nacl-irt.h used to build libc, by rewriting foo_t and struct bar
+# to nacl_abi_foo_t and nacl_abi_bar_t (and eliding forward declarations).
+# It doesn't perturb any struct CamelCaps cases, since such names will
+# be used only in NaCl-specific interfaces.
+/^struct \([a-z][a-z]*\);$/d
+/^#include "irt\.h"$/d
+/(/!b
+s/\([a-z0-9_][a-z0-9_]*\)_t\>/nacl_abi_\1_t/g
+s/struct \([a-z0-9_][a-z0-9_]*\)/nacl_abi_\1_t/g
+s/nacl_abi_\(u*int[3264ptr]*_t\)/\1/g
+s/nacl_abi_\(nacl_irt_\)/\1/g
diff --git a/sysdeps/nacl/isatty.c b/sysdeps/nacl/isatty.c
new file mode 100644
index 0000000000..fc1a686bae
--- /dev/null
+++ b/sysdeps/nacl/isatty.c
@@ -0,0 +1,38 @@
+/* Determine if a file descriptor refers to a terminal.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Return 1 if FD is a terminal, 0 if not.  */
+int
+__isatty (int fd)
+{
+  int result;
+  int error = __nacl_irt_dev_fdio.isatty (fd, &result);
+  if (error == 0)
+    {
+      if (result)
+	return 1;
+      error = ENOTTY;
+    }
+  errno = error;
+  return 0;
+}
+weak_alias (__isatty, isatty)
diff --git a/sysdeps/nacl/kernel-features.h b/sysdeps/nacl/kernel-features.h
new file mode 100644
index 0000000000..3ae983d873
--- /dev/null
+++ b/sysdeps/nacl/kernel-features.h
@@ -0,0 +1,28 @@
+/* Set flags signalling availability of certain operating system features.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file can define __ASSUME_* macros checked by certain source files.
+   Almost none of these are used outside of sysdeps/unix/sysv/linux code.
+   But those referring to POSIX-level features like O_* flags can be.  */
+
+#define __ASSUME_O_CLOEXEC	1
+
+/*
+#define __ASSUME_DUP3		1
+#define __ASSUME_ACCEPT4	1
+*/
diff --git a/sysdeps/nacl/ldsodefs.h b/sysdeps/nacl/ldsodefs.h
new file mode 100644
index 0000000000..383ced5612
--- /dev/null
+++ b/sysdeps/nacl/ldsodefs.h
@@ -0,0 +1,35 @@
+/* Run-time dynamic linker data structures for loaded ELF shared objects.  NaCl.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef	_LDSODEFS_H
+
+/* Get the real definitions.  */
+#include_next <ldsodefs.h>
+
+/* Now define our stuff.  */
+
+/* We have the auxiliary vector.  */
+#define HAVE_AUX_VECTOR	1
+
+/* Used by static binaries to check the auxiliary vector.  */
+extern void _dl_aux_init (ElfW(auxv_t) *av) internal_function;
+
+/* Initialization which is normally done by the dynamic linker.  */
+extern void _dl_non_dynamic_init (void) internal_function;
+
+#endif  /* ldsodefs.h */
diff --git a/sysdeps/nacl/libc-start.c b/sysdeps/nacl/libc-start.c
new file mode 100644
index 0000000000..dadd18037a
--- /dev/null
+++ b/sysdeps/nacl/libc-start.c
@@ -0,0 +1,4 @@
+/* We can compute the location of auxv without a loop, so we might as well
+   pass it in.  */
+#define LIBC_START_MAIN_AUXVEC_ARG
+#include <csu/libc-start.c>
diff --git a/sysdeps/nacl/link.c b/sysdeps/nacl/link.c
new file mode 100644
index 0000000000..49f071f3d9
--- /dev/null
+++ b/sysdeps/nacl/link.c
@@ -0,0 +1,28 @@
+/* Make a hard link.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Make a link to FROM called TO.  */
+int
+__link (const char *from, const char *to)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.link (from, to), 0);
+}
+weak_alias (__link, link)
diff --git a/sysdeps/nacl/lowlevellock-futex.h b/sysdeps/nacl/lowlevellock-futex.h
new file mode 100644
index 0000000000..8d888a2e72
--- /dev/null
+++ b/sysdeps/nacl/lowlevellock-futex.h
@@ -0,0 +1,87 @@
+/* Low-level locking access to futex facilities.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _LOWLEVELLOCK_FUTEX_H
+#define _LOWLEVELLOCK_FUTEX_H   1
+
+#include <nacl-interfaces.h>
+#include <time.h>
+
+
+#pragma GCC diagnostic ignored "-Wunused-value" /* XXX */
+
+/* Values for 'private' parameter of locking macros.  Note pthreadP.h
+   optimizes for these exact values, though they are not required.  */
+#define LLL_PRIVATE     0
+#define LLL_SHARED      128
+
+#define FUTEX_PRIVATE_FLAG	0       /* XXX */
+
+
+/* Wait while *FUTEXP == VAL for an lll_futex_wake call on FUTEXP.  */
+#define lll_futex_wait(futexp, val, private) \
+  (- __nacl_irt_futex.futex_wait_abs ((volatile int *) (futexp), val, NULL))
+
+/* Wait until a lll_futex_wake call on FUTEXP, or TIMEOUT elapses.  */
+#define lll_futex_timed_wait(futexp, val, timeout, private)             \
+  ({                                                                    \
+    /* This timeout is relative, but the IRT call wants it absolute.  */ \
+    const struct timespec *_to = (timeout);                             \
+    struct timespec _ts;                                                \
+    int _err = 0;                                                       \
+    if (_to != NULL                                                     \
+        && __glibc_likely ((_err = __nacl_irt_clock.clock_gettime	\
+                            (CLOCK_REALTIME, &_ts)) == 0))		\
+      {                                                                 \
+        _ts.tv_sec -= _to->tv_sec;                                      \
+        _ts.tv_nsec -= _to->tv_nsec;                                    \
+        while (_ts.tv_nsec < 0)                                         \
+          {                                                             \
+            _ts.tv_nsec += 1000000000;                                  \
+            --_ts.tv_sec;                                               \
+          }                                                             \
+        _to = &_ts;                                                     \
+      }                                                                 \
+    if (_err == 0)                                                      \
+      _err = __nacl_irt_futex.futex_wait_abs				\
+        ((volatile int *) (futexp), val, _to);                          \
+    -_err;                                                              \
+  })
+
+/* Wake up up to NR waiters on FUTEXP.  */
+#define lll_futex_wake(futexp, nr, private)                     \
+  ({                                                            \
+    int _woken;                                                 \
+    - __nacl_irt_futex.futex_wake ((volatile int *) (futexp), nr, &_woken); \
+  })
+
+/* NaCl does not support the requeue operation.  The only use of this is in
+   pthread_cond_broadcast, which handles an error return by falling back to
+   plain lll_futex_wake.  */
+#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
+  ((futexp), (nr_wake), (nr_move), (mutex), (val), (private), -ENOSYS)
+
+/* NaCl does not support the special wake-unlock operation.  The only use
+   of this is in pthread_cond_signal, which handles an error return by
+   falling back to plain lll_futex_wake.  */
+/* Wake up up to NR_WAKE waiters on FUTEXP and NR_WAKE2 on FUTEXP2.  */
+#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
+  ((futexp), (nr_wake), (nr_wake2), (futexp2), (private), -ENOSYS)
+
+
+#endif  /* lowlevellock-futex.h */
diff --git a/sysdeps/nacl/lseek.c b/sysdeps/nacl/lseek.c
new file mode 100644
index 0000000000..6451eb50d5
--- /dev/null
+++ b/sysdeps/nacl/lseek.c
@@ -0,0 +1,43 @@
+/* lseek -- Move the file position of a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+
+/* Seek to OFFSET on FD, starting from WHENCE.  */
+off_t
+__libc_lseek (int fd, off_t offset, int whence)
+{
+  off_t result;
+  int error = __nacl_irt_fdio.seek (fd, offset, whence, &result);
+  if (error)
+    {
+      __set_errno (error);
+      return -1;
+    }
+  return result;
+}
+libc_hidden_def (__lseek)
+weak_alias (__libc_lseek, __lseek)
+weak_alias (__libc_lseek, lseek)
+
+/* Since off64_t is the same as off_t, lseek64 is just an alias.  */
+weak_alias (__libc_lseek, __libc_lseek64)
+weak_alias (__libc_lseek, __lseek64)
+weak_alias (__libc_lseek, lseek64)
diff --git a/sysdeps/nacl/lseek64.c b/sysdeps/nacl/lseek64.c
new file mode 100644
index 0000000000..6f42ee6584
--- /dev/null
+++ b/sysdeps/nacl/lseek64.c
@@ -0,0 +1 @@
+/* lseek.c defines lseek64 as an alias.  */
diff --git a/sysdeps/nacl/lxstat.c b/sysdeps/nacl/lxstat.c
new file mode 100644
index 0000000000..b14708529d
--- /dev/null
+++ b/sysdeps/nacl/lxstat.c
@@ -0,0 +1,46 @@
+/* Get stat information from a file name  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Avoid the declaration so the compiler doesn't complain about the alias
+   with a different type signature.  It doesn't know that 'struct stat'
+   and 'struct stat64' are ABI-compatible.  */
+#define __lxstat64 __lxstat64_avoid
+#include <sys/stat.h>
+#undef  __lxstat64
+
+#include <errno.h>
+#include <stddef.h>
+
+#include <xstatconv.h>
+
+#undef  lstat
+
+/* Get file attributes about FILE and put them in BUF.
+   If FILE is a symbolic link, do not follow it.  */
+int
+__lxstat (int vers, const char *file, struct stat *buf)
+{
+  nacl_abi_stat_t abi_buf;
+  return NACL_CALL (__nacl_irt_dev_filename.lstat (file, &abi_buf),
+                    __xstat_conv (vers, &abi_buf, buf));
+}
+hidden_def (__lxstat)
+weak_alias (__lxstat, _lxstat)
+
+strong_alias (__lxstat, __lxstat64)
+hidden_ver (__lxstat, __lxstat64)
diff --git a/sysdeps/nacl/lxstat64.c b/sysdeps/nacl/lxstat64.c
new file mode 100644
index 0000000000..ca4ecd2be5
--- /dev/null
+++ b/sysdeps/nacl/lxstat64.c
@@ -0,0 +1 @@
+/* lxstat.c defines __lxstat64 as an alias.  */
diff --git a/sysdeps/nacl/mkdir.c b/sysdeps/nacl/mkdir.c
new file mode 100644
index 0000000000..73b4748bba
--- /dev/null
+++ b/sysdeps/nacl/mkdir.c
@@ -0,0 +1,28 @@
+/* Make a directory.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/stat.h>
+#include <nacl-interfaces.h>
+
+/* Create a directory named PATH with protections MODE.  */
+int
+__mkdir (const char *path, mode_t mode)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.mkdir (path, mode), 0);
+}
+weak_alias (__mkdir, mkdir)
diff --git a/sysdeps/nacl/mmap.c b/sysdeps/nacl/mmap.c
new file mode 100644
index 0000000000..e9c53267cb
--- /dev/null
+++ b/sysdeps/nacl/mmap.c
@@ -0,0 +1,49 @@
+/* Map addresses from a file or anonymous memory.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/mman.h>
+#include <nacl-interfaces.h>
+
+
+/* Map addresses starting near ADDR and extending for LEN bytes.  From
+   OFFSET into the file FD describes according to PROT and FLAGS.  If ADDR
+   is nonzero, it is the desired mapping address.  If the MAP_FIXED bit is
+   set in FLAGS, the mapping will be at ADDR exactly (which must be
+   page-aligned); otherwise the system chooses a convenient nearby address.
+   The return value is the actual mapping address chosen or MAP_FAILED
+   for errors (in which case `errno' is set).  A successful `mmap' call
+   deallocates any previous mapping for the affected region.  */
+
+__ptr_t
+__mmap (__ptr_t addr, size_t len, int prot, int flags, int fd, off_t offset)
+{
+  int error = __nacl_irt_memory.mmap (&addr, len, prot, flags, fd, offset);
+  if (error)
+    {
+      errno = error;
+      return MAP_FAILED;
+    }
+  return addr;
+}
+weak_alias (__mmap, mmap)
+
+
+/* Since off64_t is the same as off_t, mmap64 is just an alias.  */
+strong_alias (__mmap, __mmap64)
+weak_alias (__mmap, mmap64)
diff --git a/sysdeps/nacl/mmap64.c b/sysdeps/nacl/mmap64.c
new file mode 100644
index 0000000000..e8775a6931
--- /dev/null
+++ b/sysdeps/nacl/mmap64.c
@@ -0,0 +1 @@
+/* mmap.c defines mmap64 as an alias.  */
diff --git a/sysdeps/nacl/mprotect.c b/sysdeps/nacl/mprotect.c
new file mode 100644
index 0000000000..6fd6a4dc06
--- /dev/null
+++ b/sysdeps/nacl/mprotect.c
@@ -0,0 +1,33 @@
+/* Change memory protections on pages.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <nacl-interfaces.h>
+
+
+/* Change the memory protection of the region starting at ADDR and
+   extending LEN bytes to PROT.  Returns 0 if successful, -1 for errors
+   (and sets errno).  */
+
+int
+__mprotect (__ptr_t addr, size_t len, int prot)
+{
+  return NACL_CALL (__nacl_irt_memory.mprotect (addr, len, prot), 0);
+}
+weak_alias (__mprotect, mprotect)
diff --git a/sysdeps/nacl/munmap.c b/sysdeps/nacl/munmap.c
new file mode 100644
index 0000000000..194e409ae8
--- /dev/null
+++ b/sysdeps/nacl/munmap.c
@@ -0,0 +1,32 @@
+/* Deallocate a region of pages.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/mman.h>
+#include <nacl-interfaces.h>
+
+
+/* Deallocate any mapping for the region starting at ADDR and extending LEN
+   bytes.  Returns 0 if successful, -1 for errors (and sets errno).  */
+
+int
+__munmap (__ptr_t addr, size_t len)
+{
+  return NACL_CALL (__nacl_irt_memory.munmap (addr, len), 0);
+}
+
+weak_alias (__munmap, munmap)
diff --git a/sysdeps/nacl/nacl-after-link.sh b/sysdeps/nacl/nacl-after-link.sh
new file mode 100755
index 0000000000..199f1b89ac
--- /dev/null
+++ b/sysdeps/nacl/nacl-after-link.sh
@@ -0,0 +1,69 @@
+#!/bin/sh
+# Script to validate NaCl binaries after linking.
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+# See sysdeps/nacl/Makefile for how this script is invoked.
+READELF="$1"
+binary="$2"
+
+if [ -z "$NACL_SDK_ROOT" ]; then
+  echo >&2 "$0: NACL_SDK_ROOT must be set in the environment"
+  exit 77
+fi
+
+ncval="${NACL_SDK_ROOT}/tools/ncval"
+
+if [ ! -x "$ncval" ]; then
+  echo >&2 "$0: No ncval binary in $ncval"
+  exit 77
+fi
+
+"${READELF}" -Wl "$binary" | awk '
+BEGIN { saw_load = saw_text = 0 }
+$1 == "LOAD" {
+  saw_load = 1;
+  if (/ R.E /) saw_code = 1;
+}
+END {
+  exit (saw_code ? 11 : saw_load ? 22 : 1);
+}
+'
+case $? in
+11)
+  # We saw a code segment, so we can try ncval.
+  ;;
+22)
+  # We saw LOAD segments but none of them were code.
+  echo >&2 "+++ No code: $binary"
+  exit 0
+  ;;
+*)
+  # Something funny going on.
+  echo >&2 "*** Failed to analyze: $binary"
+  exit 2
+  ;;
+esac
+
+if "$ncval" "$binary"; then
+  echo >&2 "+++ Validated: $binary"
+  exit 0
+else
+  echo >&2 "*** Validation failed: $binary"
+  exit 2
+fi
diff --git a/sysdeps/nacl/nacl-interface-list.h b/sysdeps/nacl/nacl-interface-list.h
new file mode 100644
index 0000000000..d09814739a
--- /dev/null
+++ b/sysdeps/nacl/nacl-interface-list.h
@@ -0,0 +1,47 @@
+/* List of NaCl interface tables used in libraries.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_BASIC_v0_1, nacl_irt_basic)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_FDIO_v0_1, nacl_irt_fdio)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_FILENAME_v0_1, nacl_irt_filename)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_MEMORY_v0_3, nacl_irt_memory)
+NACL_MANDATORY_INTERFACE (libc,
+			  NACL_IRT_THREAD_v0_1, nacl_irt_thread)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_FUTEX_v0_1, nacl_irt_futex)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_TLS_v0_1, nacl_irt_tls)
+NACL_MANDATORY_INTERFACE (libc,
+			  NACL_IRT_RESOURCE_OPEN_v0_1, nacl_irt_resource_open)
+NACL_MANDATORY_INTERFACE (rtld,
+			  NACL_IRT_CODE_DATA_ALLOC_v0_1,
+			  nacl_irt_code_data_alloc)
+NACL_OPTIONAL_INTERFACE (libc,
+			 NACL_IRT_CLOCK_v0_1, nacl_irt_clock)
+NACL_OPTIONAL_INTERFACE (rtld,
+			 NACL_IRT_DYNCODE_v0_1, nacl_irt_dyncode)
+NACL_OPTIONAL_INTERFACE (rtld,
+			 NACL_IRT_DEV_GETPID_v0_1, nacl_irt_dev_getpid)
+NACL_OPTIONAL_INTERFACE (rtld,
+			 NACL_IRT_DEV_FILENAME_v0_3, nacl_irt_dev_filename)
+NACL_OPTIONAL_INTERFACE (libc,
+			 NACL_IRT_DEV_FDIO_v0_3, nacl_irt_dev_fdio)
diff --git a/sysdeps/nacl/nacl-interface-table.c b/sysdeps/nacl/nacl-interface-table.c
new file mode 100644
index 0000000000..e5401983f9
--- /dev/null
+++ b/sysdeps/nacl/nacl-interface-table.c
@@ -0,0 +1,43 @@
+/* Define one NaCl interface table.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "nacl-interfaces.h"
+
+#define PASTE(a, b)     PASTE_1 (a, b)
+#define PASTE_1(a, b)   a##b
+#define STRINGIFY(x)    STRINGIFY_1 (x)
+#define STRINGIFY_1(x)  #x
+
+#if IS_IN (rtld) && PASTE (MODULE_, INTERFACE_MODULE) != MODULE_rtld
+# error "This interface is also needed in rtld."
+#endif
+
+#define SECTION(which) \
+  section ("nacl_"  STRINGIFY (INTERFACE_CATEGORY) "_interface_" #which)
+
+static const struct nacl_interface PASTE (desc_, INTERFACE_TYPE)
+  __attribute__ ((used, SECTION (names))) =
+{
+  .table_size = sizeof (struct INTERFACE_TYPE),
+  .namelen = sizeof INTERFACE_STRING,
+  .name = INTERFACE_STRING
+};
+
+struct INTERFACE_TYPE PASTE (__, INTERFACE_TYPE)
+  __attribute__ ((SECTION (tables)));
+PASTE (INTERFACE_MODULE, _hidden_data_def) (PASTE (__, INTERFACE_TYPE))
diff --git a/sysdeps/nacl/nacl-interfaces.c b/sysdeps/nacl/nacl-interfaces.c
new file mode 100644
index 0000000000..cb0dcd0bc8
--- /dev/null
+++ b/sysdeps/nacl/nacl-interfaces.c
@@ -0,0 +1,123 @@
+/* Using NaCl interface tables.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <nacl-interfaces.h>
+#include <ldsodefs.h>
+
+
+/* These magic symbols are provided implicitly by the linker to
+   give us the bounds of the specially-named sections.  */
+
+extern const struct nacl_interface __start_nacl_mandatory_interface_names[]
+  attribute_hidden;
+extern const struct nacl_interface __stop_nacl_mandatory_interface_names[]
+  attribute_hidden;
+
+extern uintptr_t __start_nacl_mandatory_interface_tables[]
+  attribute_hidden;
+extern uintptr_t __stop_nacl_mandatory_interface_tables[]
+  attribute_hidden;
+
+/* We use weak references for the optional ones, since they
+   might not be included at all in any given statically-linked program.  */
+
+extern const struct nacl_interface __start_nacl_optional_interface_names[]
+  attribute_hidden __attribute__ ((weak));
+extern const struct nacl_interface __stop_nacl_optional_interface_names[]
+  attribute_hidden __attribute__ ((weak));
+
+extern uintptr_t __start_nacl_optional_interface_tables[]
+  attribute_hidden __attribute__ ((weak));
+extern uintptr_t __stop_nacl_optional_interface_tables[]
+  attribute_hidden __attribute__ ((weak));
+
+static uintptr_t *
+next_nacl_table (uintptr_t *t, const struct nacl_interface *i)
+{
+  return (void *) t + i->table_size;
+}
+
+static void __attribute__ ((noreturn))
+missing_mandatory_interface (const struct nacl_interface *i)
+{
+  static const char before[] =
+    "FATAL: NaCl IRT interface query failed for essential interface \"";
+  static const char after[] =
+    "\"\n";
+
+  if (__nacl_irt_fdio.write != NULL)
+    {
+      size_t wrote;
+      (*__nacl_irt_fdio.write) (2, before, sizeof before - 1, &wrote);
+      (*__nacl_irt_fdio.write) (2, i->name, i->namelen - 1, &wrote);
+      (*__nacl_irt_fdio.write) (2, after, sizeof after - 1, &wrote);
+    }
+
+  if (__nacl_irt_basic.exit != NULL)
+    (*__nacl_irt_basic.exit) (-1);
+
+  __builtin_trap ();
+}
+
+static void
+initialize_mandatory_interfaces (void)
+{
+  const struct nacl_interface *i = __start_nacl_mandatory_interface_names;
+  uintptr_t *t = __start_nacl_mandatory_interface_tables;
+  while (i < __stop_nacl_mandatory_interface_names)
+    {
+      if (__nacl_irt_query (i->name, t, i->table_size) != i->table_size)
+	missing_mandatory_interface (i);
+
+      t = next_nacl_table (t, i);
+      i = next_nacl_interface (i);
+    }
+}
+
+
+static int
+nacl_missing_optional_interface (void)
+{
+  return ENOSYS;
+}
+
+static void
+initialize_optional_interfaces (void)
+{
+  const struct nacl_interface *i = __start_nacl_optional_interface_names;
+  uintptr_t *t = __start_nacl_optional_interface_tables;
+  while (i < __stop_nacl_optional_interface_names)
+    {
+      size_t filled = __nacl_irt_query (i->name, t, i->table_size);
+      if (filled != i->table_size)
+	for (size_t slot = 0; slot < i->table_size / sizeof *t; ++slot)
+	  t[slot] = (uintptr_t) &nacl_missing_optional_interface;
+
+      t = next_nacl_table (t, i);
+      i = next_nacl_interface (i);
+    }
+}
+
+
+void attribute_hidden
+__nacl_initialize_interfaces (void)
+{
+  initialize_mandatory_interfaces ();
+  initialize_optional_interfaces ();
+}
diff --git a/sysdeps/nacl/nacl-interfaces.h b/sysdeps/nacl/nacl-interfaces.h
new file mode 100644
index 0000000000..8d28e1a6df
--- /dev/null
+++ b/sysdeps/nacl/nacl-interfaces.h
@@ -0,0 +1,108 @@
+/* Using NaCl interface tables.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _NACL_INTERFACES_H
+#define _NACL_INTERFACES_H	1
+
+#include <errno.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+
+/* <nacl-irt.h> is massaged from native_client/src/untrusted/irt/irt.h so
+   that it uses nacl_abi_*_t type names.  We must define those types first.  */
+
+/* These are the same in the IRT ABI as in the libc ABI.  */
+typedef blksize_t nacl_abi_blksize_t;
+typedef dev_t nacl_abi_dev_t;
+typedef gid_t nacl_abi_gid_t;
+typedef ino_t nacl_abi_ino_t;
+typedef mode_t nacl_abi_mode_t;
+typedef nlink_t nacl_abi_nlink_t;
+typedef size_t nacl_abi_size_t;
+typedef time_t nacl_abi_time_t;
+typedef uid_t nacl_abi_uid_t;
+typedef struct dirent nacl_abi_dirent_t;
+typedef struct timeval nacl_abi_timeval_t;
+typedef struct timespec nacl_abi_timespec_t;
+
+/* XXX change clock_t? */
+typedef uint32_t nacl_abi_clock_t;
+
+typedef int32_t nacl_abi_blkcnt_t;
+
+/* This is different by design.  */
+typedef struct nacl_abi_stat nacl_abi_stat_t;
+
+#include <nacl-irt.h>
+
+/* This is how we access the IRT interface-query function.
+   This formulation makes it usable as if it were a function name.  */
+#define __nacl_irt_query	(*(TYPE_nacl_irt_query) GLRO(dl_sysinfo))
+
+
+/* This describes one IRT (or IRT-like) interface that libc uses.
+   This structure contains no pointers, so it can go into rodata
+   without relocs.  Instead, the actual tables we use for these
+   interfaces live in a parallel section in writable data.  */
+struct nacl_interface {
+  size_t table_size;
+  size_t namelen;
+  char name[];
+};
+
+/* Increment for 'const struct nacl_interface *' pointers.  */
+static inline const struct nacl_interface *
+next_nacl_interface (const struct nacl_interface *i)
+{
+  uintptr_t align = __alignof (*i);
+  return (const void *) (((uintptr_t) &i->name[i->namelen] + align - 1)
+                         & -align);
+}
+
+#if IS_IN (libpthread)
+# define libpthread_hidden_proto(name)	hidden_proto (name)
+#else
+# define libpthread_hidden_proto(name)
+#endif
+
+#define DECLARE_INTERFACE(module, type) \
+  extern struct type __##type; module##_hidden_proto (__##type);
+
+#define NACL_MANDATORY_INTERFACE(module, id, type)	\
+  DECLARE_INTERFACE (module, type)
+#define NACL_OPTIONAL_INTERFACE(module, id, type)	\
+  DECLARE_INTERFACE (module, type)
+#include "nacl-interface-list.h"
+#undef	NACL_MANDATORY_INTERFACE
+#undef	NACL_OPTIONAL_INTERFACE
+
+extern void __nacl_initialize_interfaces (void) attribute_hidden;
+
+/* Convenience function for handling IRT call return values.  */
+static inline int
+__nacl_fail (int err)
+{
+  errno = err;
+  return -1;
+}
+
+#define NACL_CALL(err, val) \
+  ({ int _err = (err); _err ? __nacl_fail (_err) : (val); })
+
+#endif  /* nacl-interfaces.h */
diff --git a/sysdeps/nacl/nacl-interfaces.mk.in b/sysdeps/nacl/nacl-interfaces.mk.in
new file mode 100644
index 0000000000..92ff3c6afe
--- /dev/null
+++ b/sysdeps/nacl/nacl-interfaces.mk.in
@@ -0,0 +1,25 @@
+/* Might as well be -*- C -*-.
+
+   This generates a makefile that sets the variable pairs
+   nacl-MODULE-mandatory-interfaces and nacl-MODULE-optional-interfaces
+   based on the nacl-interface-list.h list.  */
+
+%define NACL_MANDATORY_INTERFACE(module, id, type)       \
+  nacl-mandatory-interfaces += module-type
+%define NACL_OPTIONAL_INTERFACE(module, id, type) \
+  nacl-optional-interfaces += module-type
+
+%include "nacl-interface-list.h"
+
+%undef NACL_MANDATORY_INTERFACE
+%undef NACL_OPTIONAL_INTERFACE
+
+%define NACL_MANDATORY_INTERFACE(module, id, type)	\
+  nacl-module-type-string := id
+%define NACL_OPTIONAL_INTERFACE(module, id, type)	\
+  nacl-module-type-string := id
+
+%include "nacl-interface-list.h"
+
+%undef NACL_MANDATORY_INTERFACE
+%undef NACL_OPTIONAL_INTERFACE
diff --git a/sysdeps/nacl/nacl-test-wrapper.sh b/sysdeps/nacl/nacl-test-wrapper.sh
new file mode 100755
index 0000000000..0e05813143
--- /dev/null
+++ b/sysdeps/nacl/nacl-test-wrapper.sh
@@ -0,0 +1,280 @@
+#!/bin/bash
+# test-wrapper script for NaCl.
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+progname="$(basename "$0")"
+
+usage="usage: ${progname} --arch=ARCH [VAR=VAL...] COMMAND ..."
+help="
+"
+
+use_bootstrap=true
+arch=
+env=()
+envi=0
+while [ $# -gt 0 ]; do
+  case "$1" in
+
+    --help)
+      echo "$usage"
+      echo "$help"
+      exit 0
+      ;;
+
+    --arch=*)
+      arch="${1#--arch=}"
+      shift
+      ;;
+
+    *=*)
+      env[envi++]='-E'
+      env[envi++]="$1"
+      shift
+      ;;
+
+    --)
+      shift
+      break
+      ;;
+
+    *)
+      break
+      ;;
+  esac
+done
+
+if [ $# -lt 1 -o -z "$arch" ]; then
+  echo "$usage" >&2
+  echo "Type '${progname} --help' for more detailed help." >&2
+  exit 1
+fi
+
+test_args=("$@")
+
+if [ -z "$NACL_SDK_ROOT" ]; then
+  echo >&2 "$0: NACL_SDK_ROOT must be set in the environment"
+  exit 77
+fi
+
+# We use a handful of things from the NaCl SDK, or at least
+# from a directory matching the layout of the NaCl SDK.
+sdk_tools="${NACL_SDK_ROOT}/tools"
+
+NACL_BOOTSTRAP="${sdk_tools}/nacl_helper_bootstrap_${arch}"
+NACL_SEL_LDR="${sdk_tools}/sel_ldr_${arch}"
+NACL_IRT="${sdk_tools}/irt_core_${arch}.nexe"
+NACL_LOADER="${sdk_tools}/loader_${arch}.nexe"
+
+if [ ! -x "$NACL_BOOTSTRAP" -o ! -x "$NACL_SEL_LDR" ]; then
+  echo >&2 "$0: sel_ldr_${arch} and/or nacl_helper_bootstrap_${arch} missing"
+  echo >&2 "$0: from directory $sdk_tools"
+  exit 77
+fi
+
+if [ ! -r "$NACL_IRT" -o ! -r "$NACL_LOADER" ]; then
+  echo >&2 "$0: irt_core_${arch}.nexe and/or loader_${arch}.nexe missing"
+  echo >&2 "$0: from directory $sdk_tools"
+  exit 77
+fi
+
+# Figure out if we are building for the native machine or not.
+# If not, we'll run sel_ldr under qemu.
+decide_use_emulator()
+{
+  local arg
+  for arg; do
+    if [[ "$(uname -m)" = "$1" ]]; then
+      return
+    fi
+  done
+  use_emulator=true
+}
+
+use_emulator=false
+case "$arch" in
+arm)
+  decide_use_emulator 'arm*'
+  emulator=(qemu-arm -cpu cortex-a15 -L "${sdk_tools}/arm_trusted")
+  ;;
+x86_32)
+  decide_use_emulator 'i?86' 'x86_64*'
+  emulator=(qemu-i386)
+  ;;
+x86_64)
+  decide_use_emulator 'x86_64*'
+  emulator=(qemu-x86_64)
+  ;;
+esac
+
+if $use_emulator; then
+  ldr_args=('-Q')
+  emulator_factor=10
+else
+  emulator=()
+  ldr_args=()
+  emulator_factor=1
+fi
+
+if $use_bootstrap; then
+  ldr=(
+    "${NACL_BOOTSTRAP}"
+    "${NACL_SEL_LDR}"
+    '--r_debug=0xXXXXXXXXXXXXXXXX'
+    '--reserved_at_zero=0xXXXXXXXXXXXXXXXX'
+  )
+else
+  ldr=("${NACL_SEL_LDR}")
+fi
+
+static=true
+case "$1" in
+*/ld-nacl*) static=false ;;
+esac
+
+if $static; then
+  loader=()
+else
+  loader=(-f "${NACL_LOADER}")
+fi
+
+run_test()
+{
+  local test_fifo="$1"
+  local cmd=(
+    "${emulator[@]}" "${ldr[@]}" -q -S -a "${ldr_args[@]}" -B "${NACL_IRT}"
+    "${loader[@]}" "${env[@]}" -E TEST_DIRECT="$test_fifo" -- "${test_args[@]}"
+  )
+  if [ "${NACLVERBOSITY:+set}" = set ]; then
+    "${cmd[@]}"
+  else
+    NACLLOG=/dev/null "${cmd[@]}"
+  fi
+}
+
+temp_files=()
+test_fifo=
+do_cleanup()
+{
+  rm -rf "$test_fifo" "${temp_files[@]}"
+}
+trap do_cleanup EXIT HUP INT TERM
+
+# Create a named pipe to receive the TEST_DIRECT information from the test
+# program.
+test_fifo=${TMPDIR:-/tmp}/libc-test-fifo.$$
+rm -f "$test_fifo"
+mkfifo "$test_fifo" || {
+  echo "Cannot create test FIFO '$test_fifo'"
+  exit 1
+}
+
+# Run the test in the background, so we can implement a timeout.
+# The no-op redirection defeats the default behavior of "< /dev/null"
+# for a background command.
+run_test "$test_fifo" <&0 & test_pid=$!
+
+# Set up a short timeout before we read from the FIFO, in case
+# the program doesn't actually write to the FIFO at all (it is
+# not a test-skeleton.c program, or it dies very early).
+no_skeleton=false
+script_pid=$$
+trap 'no_skeleton=true' USR1
+(sleep 2; kill -USR1 $script_pid) 2> /dev/null &
+
+# The test should first write into the FIFO to describe its expectations.
+# Our open-for-reading of the FIFO will block until the test starts up and
+# opens it for writing.  Then our reads will block until the test finishes
+# writing out info and closes the FIFO.  At that point we will have
+# collected (and evaluated) what it emitted.  It sets these variables:
+#	timeout=%u
+#	timeoutfactor=%u
+#	exit=%u
+#	signal=%s
+unset exit signal
+. "$test_fifo" 2> /dev/null
+
+# If we got this far, either the 'no_skeleton=true' watchdog already
+# fired, or else we don't want it to.
+trap '' USR1
+
+if $no_skeleton; then
+  # We hit the timeout, so we didn't get full information about test
+  # expectations.  Reset any partial results we may have gotten.
+  unset exit signal
+else
+  # Now we know the expected timeout, so we can start the timer running.
+  ((sleep_time = timeout * timeoutfactor * emulator_factor))
+
+  # Now start a background subshell to enforce the timeout.
+  (sleep "$sleep_time"; kill -ALRM $test_pid) 2> /dev/null &
+fi
+
+# This corresponds to '#ifdef EXPECTED_STATUS' in test-skeleton.c.
+expected_status()
+{
+  test "${exit+yes}" = yes
+}
+# This corresponds to '#ifdef EXPECTED_SIGNAL' in test-skeleton.c.
+expected_signal()
+{
+  test "${signal+yes}" = yes
+}
+# This corresponds to 'if (WIFEXITED (status))' in test-skeleton.c.
+wifexited()
+{
+  test $test_rc -lt 128
+}
+
+# Now wait for the test process to finish.
+wait $test_pid
+test_rc=$?
+
+# This exactly duplicates the logic in test-skeleton.c.
+if wifexited; then
+  if ! expected_status; then
+    if ! expected_signal; then
+      # Simply exit with the return value of the test.  */
+      exit $test_rc
+    else
+      echo "Expected signal '${signal}' from child, got none"
+      exit 1
+    fi
+  else
+    if [ $test_rc -ne $exit ]; then
+      echo "Expected status $exit, got $test_rc"
+      exit 1
+    fi
+    exit 0
+  fi
+else
+  # Process was killed by timer or other signal.
+  ((test_signal = test_rc > 192 ? 256 - test_rc : test_rc - 128 ))
+  test_signame=$(kill -l "$test_signal")
+  if ! expected_signal; then
+    echo "Didn't expect signal from child; got '${test_signame}'"
+    exit 1
+  else
+    if [ "$test_signame" != "$signal" ]; then
+      echo "\
+Incorrect signal from child: got '${test_signame}', need '${signal}'"
+      exit 1
+    fi
+    exit 0
+  fi
+fi
diff --git a/sysdeps/nacl/nacl_interface_query.c b/sysdeps/nacl/nacl_interface_query.c
new file mode 100644
index 0000000000..cae876b3b8
--- /dev/null
+++ b/sysdeps/nacl/nacl_interface_query.c
@@ -0,0 +1,49 @@
+/* NaCl function exposing IRT interface query.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <nacl-interfaces.h>
+#include <ldsodefs.h>
+
+#ifdef SHARED
+
+/* We can define this trivially using IFUNC rather than a wrapper
+   because we absolutely require that we get the IRT interface query
+   function pointer via AT_SYSINFO.  */
+
+extern TYPE_nacl_irt_query nacl_interface_query_ifunc (void)
+  asm ("nacl_interface_query");
+
+TYPE_nacl_irt_query
+nacl_interface_query_ifunc (void)
+{
+  return &__nacl_irt_query;
+}
+asm (".type nacl_interface_query, %gnu_indirect_function");
+
+#else
+
+/* In the static library, using IFUNC is just extra overhead.  */
+
+size_t
+nacl_interface_query (const char *interface_ident,
+                      void *table, size_t tablesize)
+{
+  return __nacl_irt_query (interface_ident, table, tablesize);
+}
+
+#endif
diff --git a/sysdeps/nacl/nanosleep.c b/sysdeps/nacl/nanosleep.c
new file mode 100644
index 0000000000..cc60a466c8
--- /dev/null
+++ b/sysdeps/nacl/nanosleep.c
@@ -0,0 +1,33 @@
+/* nanosleep -- Sleep for a duration given in nanoseconds.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <time.h>
+#include <nacl-interfaces.h>
+
+
+/* Pause execution for a number of nanoseconds.  */
+int
+__libc_nanosleep (const struct timespec *requested_time,
+                  struct timespec *remaining)
+{
+  return NACL_CALL (__nacl_irt_basic.nanosleep (requested_time, remaining), 0);
+}
+
+weak_alias (__libc_nanosleep, __nanosleep)
+libc_hidden_def (__nanosleep)
+weak_alias (__libc_nanosleep, nanosleep)
diff --git a/sysdeps/nacl/open.c b/sysdeps/nacl/open.c
new file mode 100644
index 0000000000..cb4700ff24
--- /dev/null
+++ b/sysdeps/nacl/open.c
@@ -0,0 +1,52 @@
+/* Open a file by name.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <nacl-interfaces.h>
+
+
+/* Open FILE with access OFLAG.  If OFLAG includes O_CREAT,
+   a third argument is the file protection.  */
+int
+__libc_open (const char *file, int oflag, ...)
+{
+  mode_t mode = 0;
+
+  if (oflag & O_CREAT)
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, mode_t);
+      va_end (arg);
+    }
+
+  int fd;
+  return NACL_CALL (__nacl_irt_filename.open (file, oflag, mode, &fd), fd);
+}
+libc_hidden_def (__libc_open)
+weak_alias (__libc_open, __open)
+libc_hidden_weak (__open)
+weak_alias (__libc_open, open)
+
+/* open64 is just an alias.  */
+strong_alias (__libc_open, __libc_open64)
+strong_alias (__libc_open64, __open64)
+libc_hidden_def (__open64)
+weak_alias (__libc_open64, open64)
diff --git a/sysdeps/nacl/open64.c b/sysdeps/nacl/open64.c
new file mode 100644
index 0000000000..b3e5563cd6
--- /dev/null
+++ b/sysdeps/nacl/open64.c
@@ -0,0 +1 @@
+/* open.c defines open64 as an alias.  */
diff --git a/sysdeps/nacl/preconfigure b/sysdeps/nacl/preconfigure
new file mode 100644
index 0000000000..c700fbc2f8
--- /dev/null
+++ b/sysdeps/nacl/preconfigure
@@ -0,0 +1,7 @@
+# GNU C Library preconfigure fragment for sysdeps/nacl
+
+case "$config_machine-$config_os" in
+arm*-nacl*)
+  libc_config_ok=yes
+  ;;
+esac
diff --git a/sysdeps/nacl/profil.c b/sysdeps/nacl/profil.c
new file mode 100644
index 0000000000..701d7ad651
--- /dev/null
+++ b/sysdeps/nacl/profil.c
@@ -0,0 +1,2 @@
+/* Side-step sysdeps/posix/profil.c, which uses sigaction and setitimer.  */
+#include <gmon/profil.c>
diff --git a/sysdeps/nacl/read.c b/sysdeps/nacl/read.c
new file mode 100644
index 0000000000..fef0c82604
--- /dev/null
+++ b/sysdeps/nacl/read.c
@@ -0,0 +1,32 @@
+/* read -- Read data from a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Read NBYTES into BUF from FD.  Return the number read or -1.  */
+ssize_t
+__libc_read (int fd, void *buf, size_t nbytes)
+{
+  size_t nread;
+  return NACL_CALL (__nacl_irt_fdio.read (fd, buf, nbytes, &nread), nread);
+}
+libc_hidden_def (__libc_read)
+weak_alias (__libc_read, __read)
+libc_hidden_weak (__read)
+weak_alias (__libc_read, read)
diff --git a/sysdeps/nacl/readdir.c b/sysdeps/nacl/readdir.c
new file mode 100644
index 0000000000..a73bfe42a5
--- /dev/null
+++ b/sysdeps/nacl/readdir.c
@@ -0,0 +1,11 @@
+/* The compiler complains about aliases with nonmatching type signatures.
+   The types 'struct dirent' and 'struct dirent64' are actually identical
+   even though the compiler doesn't consider them to be.  So we hide the
+   declaration from the compiler.  */
+#define __readdir64     __avoid___readdir64_declaration
+#define readdir64       __avoid_readdir64_declaration
+#include <sysdeps/posix/readdir.c>
+#undef  __readdir64
+#undef  readdir64
+strong_alias (__readdir, __readdir64)
+weak_alias (__readdir64, readdir64)
diff --git a/sysdeps/nacl/readdir64.c b/sysdeps/nacl/readdir64.c
new file mode 100644
index 0000000000..f4806bf269
--- /dev/null
+++ b/sysdeps/nacl/readdir64.c
@@ -0,0 +1 @@
+/* readdir.c defines readdir64 as an alias.  */
diff --git a/sysdeps/nacl/readdir64_r.c b/sysdeps/nacl/readdir64_r.c
new file mode 100644
index 0000000000..c7830de559
--- /dev/null
+++ b/sysdeps/nacl/readdir64_r.c
@@ -0,0 +1 @@
+/* readdir_r.c defines readdir64_r as an alias.  */
diff --git a/sysdeps/nacl/readdir_r.c b/sysdeps/nacl/readdir_r.c
new file mode 100644
index 0000000000..3a9a71703e
--- /dev/null
+++ b/sysdeps/nacl/readdir_r.c
@@ -0,0 +1,8 @@
+/* The compiler complains about aliases with nonmatching type signatures.
+   The types 'struct dirent' and 'struct dirent64' are actually identical
+   even though the compiler doesn't consider them to be.  So we hide the
+   declaration from the compiler.  */
+#define readdir64_r     __avoid_readdir64_r_declaration
+#include <sysdeps/posix/readdir_r.c>
+#undef  readdir64_r
+weak_alias (__readdir_r, readdir64_r)
diff --git a/sysdeps/nacl/readlink.c b/sysdeps/nacl/readlink.c
new file mode 100644
index 0000000000..d1c4cadf55
--- /dev/null
+++ b/sysdeps/nacl/readlink.c
@@ -0,0 +1,32 @@
+/* Read the contents of a symbolic link.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Read the contents of the symbolic link PATH into no more than
+   LEN bytes of BUF.  The contents are not null-terminated.
+   Returns the number of characters read, or -1 for errors.  */
+ssize_t
+__readlink (const char *path, char *buf, size_t len)
+{
+  size_t nread;
+  return NACL_CALL (__nacl_irt_dev_filename.readlink (path, buf, len, &nread),
+                    nread);
+}
+weak_alias (__readlink, readlink)
diff --git a/sysdeps/nacl/rename.c b/sysdeps/nacl/rename.c
new file mode 100644
index 0000000000..8cf1b2f218
--- /dev/null
+++ b/sysdeps/nacl/rename.c
@@ -0,0 +1,27 @@
+/* Rename a file.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Rename the file OLD to NEW.  */
+int
+rename (const char *old, const char *new)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.rename (old, new), 0);
+}
diff --git a/sysdeps/nacl/rmdir.c b/sysdeps/nacl/rmdir.c
new file mode 100644
index 0000000000..917bffd4e7
--- /dev/null
+++ b/sysdeps/nacl/rmdir.c
@@ -0,0 +1,28 @@
+/* Remove a directory.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Remove the directory PATH.  */
+int
+__rmdir (const char *path)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.rmdir (path), 0);
+}
+weak_alias (__rmdir, rmdir)
diff --git a/sysdeps/nacl/sched_yield.c b/sysdeps/nacl/sched_yield.c
new file mode 100644
index 0000000000..c9c7aaa6bf
--- /dev/null
+++ b/sysdeps/nacl/sched_yield.c
@@ -0,0 +1,31 @@
+/* sched_yield -- Yield the processor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sched.h>
+#include <nacl-interfaces.h>
+
+
+/* Yield the processor.  */
+int
+__sched_yield (void)
+{
+  return NACL_CALL (__nacl_irt_basic.sched_yield (), 0);
+}
+libc_hidden_def (__sched_yield)
+weak_alias (__sched_yield, sched_yield)
diff --git a/sysdeps/nacl/shlib-versions b/sysdeps/nacl/shlib-versions
new file mode 100644
index 0000000000..c146d31b96
--- /dev/null
+++ b/sysdeps/nacl/shlib-versions
@@ -0,0 +1,9 @@
+# DEFAULT			Earliest symbol set
+# -------			-------------------
+DEFAULT				GLIBC_2.22
+
+# Library=version		Earliest symbol set (optional)
+# ---------------		------------------------------
+
+libc=0.1
+libm=0.1
diff --git a/sysdeps/nacl/sigaction.c b/sysdeps/nacl/sigaction.c
new file mode 100644
index 0000000000..898486eea5
--- /dev/null
+++ b/sysdeps/nacl/sigaction.c
@@ -0,0 +1,11 @@
+#if IS_IN (libpthread)
+
+/* This placeholder file prevents nptl/sigaction.c from being compiled.
+   For NaCl, there is no need for a separate sigaction in libpthread.  */
+
+#else
+
+/* Get the standard stub.  */
+#include <signal/sigaction.c>
+
+#endif
diff --git a/sysdeps/nacl/sprofil.c b/sysdeps/nacl/sprofil.c
new file mode 100644
index 0000000000..96d4300927
--- /dev/null
+++ b/sysdeps/nacl/sprofil.c
@@ -0,0 +1,2 @@
+/* Side-step sysdeps/posix/sprofil.c, which uses sigaction and setitimer.  */
+#include <gmon/sprofil.c>
diff --git a/sysdeps/nacl/start.c b/sysdeps/nacl/start.c
new file mode 100644
index 0000000000..a4b6dd33d4
--- /dev/null
+++ b/sysdeps/nacl/start.c
@@ -0,0 +1,73 @@
+/* Entry-point for programs.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file with other
+   programs, and to distribute those programs without any restriction
+   coming from the use of this file. (The GNU Lesser General Public
+   License restrictions do apply in other respects; for example, they
+   cover modification of the file, and distribution when not linked
+   into another program.)
+
+   Note that people who make modified versions of this file are not
+   obligated to grant this special exception for their modified
+   versions; it is their choice whether to do so. The GNU Lesser
+   General Public License gives permission to release a modified
+   version without this exception; this exception also makes it
+   possible to release a modified version which carries forward this
+   exception.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdint.h>
+#include <link.h>
+
+/* NaCl's elf32.h is incompatible with the real <elf.h>.  */
+#define NATIVE_CLIENT_SRC_INCLUDE_ELF32_H_
+#include <native_client/src/untrusted/nacl/nacl_startup.h>
+
+
+/* The application defines this, of course.  */
+extern int main (int argc, char **argv, char **envp);
+
+/* These are defined in libc.  */
+extern int __libc_csu_init (int argc, char **argv, char **envp);
+extern void __libc_csu_fini (void);
+extern void __libc_start_main (int (*main) (int, char **, char **),
+			       int argc, char **argv, ElfW(auxv_t) *auxv,
+			       int (*init) (int, char **, char **),
+			       void (*fini) (void),
+			       void (*rtld_fini) (void),
+			       void *stack_end);
+
+void
+_start (uint32_t info[])
+{
+  /* The generic code actually assumes that envp follows argv.  */
+
+  __libc_start_main (&main,
+		     nacl_startup_argc (info),
+		     nacl_startup_argv (info),
+		     nacl_startup_auxv (info),
+		     &__libc_csu_init, &__libc_csu_fini,
+		     nacl_startup_fini (info),
+		     __builtin_frame_address (0));
+
+  /* That should not return.  Make sure we crash if it did.  */
+  while (1)
+    __builtin_trap ();
+}
diff --git a/sysdeps/nacl/symlink.c b/sysdeps/nacl/symlink.c
new file mode 100644
index 0000000000..1454589fda
--- /dev/null
+++ b/sysdeps/nacl/symlink.c
@@ -0,0 +1,28 @@
+/* Make a symbolic link.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Make a symbolic link to FROM called TO.  */
+int
+__symlink (const char *from, const char *to)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.symlink (from, to), 0);
+}
+weak_alias (__symlink, symlink)
diff --git a/sysdeps/nacl/tls.h b/sysdeps/nacl/tls.h
new file mode 100644
index 0000000000..ccf4e83b43
--- /dev/null
+++ b/sysdeps/nacl/tls.h
@@ -0,0 +1,41 @@
+/* Definition for thread-local data handling.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _NACL_TLS_H
+#define _NACL_TLS_H	1
+
+#ifndef __ASSEMBLER__
+
+# include <nacl-interfaces.h>
+
+/* Code to initially initialize the thread pointer.  This might need
+   special attention since 'errno' is not yet available and if the
+   operation can cause a failure 'errno' must not be touched.  */
+# define TLS_INIT_TP(tcbp) \
+  ((*__nacl_irt_tls.tls_init) (tcbp) == 0 ? NULL : "tls_init call failed")
+
+/* Our use of dl_sysinfo is rather different from the Linux syscall
+   entry-point case.  We never need a thread-local copy of the value.  */
+# undef SETUP_THREAD_SYSINFO
+# undef CHECK_THREAD_SYSINFO
+# define SETUP_THREAD_SYSINFO(pd) ((void) (pd))
+# define CHECK_THREAD_SYSINFO(pd) ((void) (pd))
+
+#endif /* __ASSEMBLER__ */
+
+#endif  /* tls.h */
diff --git a/sysdeps/nacl/truncate.c b/sysdeps/nacl/truncate.c
new file mode 100644
index 0000000000..cdb8ac7222
--- /dev/null
+++ b/sysdeps/nacl/truncate.c
@@ -0,0 +1,32 @@
+/* Truncate a file (by name).  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Truncate PATH to LENGTH bytes.  */
+int
+__truncate (const char *path, off_t length)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.truncate (path, length), 0);
+}
+weak_alias (__truncate, truncate)
+
+/* truncate64 is the same as truncate.  */
+strong_alias (__truncate, __truncate64)
+weak_alias (__truncate64, truncate64)
diff --git a/sysdeps/nacl/truncate64.c b/sysdeps/nacl/truncate64.c
new file mode 100644
index 0000000000..729d0d01db
--- /dev/null
+++ b/sysdeps/nacl/truncate64.c
@@ -0,0 +1 @@
+/* truncate64 is the same as truncate.  */
diff --git a/sysdeps/nacl/unlink.c b/sysdeps/nacl/unlink.c
new file mode 100644
index 0000000000..6c872c2c5b
--- /dev/null
+++ b/sysdeps/nacl/unlink.c
@@ -0,0 +1,28 @@
+/* Remove a file.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Remove the link named NAME.  */
+int
+__unlink (const char *name)
+{
+  return NACL_CALL (__nacl_irt_dev_filename.unlink (name), 0);
+}
+weak_alias (__unlink, unlink)
diff --git a/sysdeps/nacl/utimes.c b/sysdeps/nacl/utimes.c
new file mode 100644
index 0000000000..1f0f08a9e0
--- /dev/null
+++ b/sysdeps/nacl/utimes.c
@@ -0,0 +1,29 @@
+/* Change the access and modification times of a file.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/time.h>
+#include <nacl-interfaces.h>
+
+/* Change the access time of FILE to TVP[0] and
+   the modification time of FILE to TVP[1].  */
+int
+__utimes (const char *file, const struct timeval tvp[2])
+{
+  return NACL_CALL (__nacl_irt_dev_filename.utimes (file, tvp), 0);
+}
+weak_alias (__utimes, utimes)
diff --git a/sysdeps/nacl/write.c b/sysdeps/nacl/write.c
new file mode 100644
index 0000000000..d4063fda8d
--- /dev/null
+++ b/sysdeps/nacl/write.c
@@ -0,0 +1,33 @@
+/* write -- Write data to a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <nacl-interfaces.h>
+
+/* Write NBYTES of BUF to FD.  Return the number written, or -1.  */
+ssize_t
+__libc_write (int fd, const void *buf, size_t nbytes)
+{
+  size_t wrote;
+  return NACL_CALL (__nacl_irt_fdio.write (fd, buf, nbytes, &wrote), wrote);
+}
+libc_hidden_def (__libc_write)
+
+weak_alias (__libc_write, __write)
+libc_hidden_weak (__write)
+weak_alias (__libc_write, write)
diff --git a/sysdeps/nacl/xstat.c b/sysdeps/nacl/xstat.c
new file mode 100644
index 0000000000..022cf0294f
--- /dev/null
+++ b/sysdeps/nacl/xstat.c
@@ -0,0 +1,45 @@
+/* Get stat information from a file name.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Avoid the declaration so the compiler doesn't complain about the alias
+   with a different type signature.  It doesn't know that 'struct stat'
+   and 'struct stat64' are ABI-compatible.  */
+#define __xstat64 __xstat64_avoid
+#include <sys/stat.h>
+#undef  __xstat64
+
+#include <errno.h>
+#include <stddef.h>
+
+#include <xstatconv.h>
+
+#undef  stat
+
+/* Get file information about FILE in BUF.  */
+int
+__xstat (int vers, const char *file, struct stat *buf)
+{
+  nacl_abi_stat_t abi_buf;
+  return NACL_CALL (__nacl_irt_filename.stat (file, &abi_buf),
+                    __xstat_conv (vers, &abi_buf, buf));
+}
+hidden_def (__xstat)
+weak_alias (__xstat, _xstat)
+
+strong_alias (__xstat, __xstat64)
+hidden_ver (__xstat, __xstat64)
diff --git a/sysdeps/nacl/xstat64.c b/sysdeps/nacl/xstat64.c
new file mode 100644
index 0000000000..47db9b9368
--- /dev/null
+++ b/sysdeps/nacl/xstat64.c
@@ -0,0 +1 @@
+/* xstat.c defines __xstat64 as an alias.  */
diff --git a/sysdeps/nacl/xstatconv.c b/sysdeps/nacl/xstatconv.c
new file mode 100644
index 0000000000..ecab76c5f0
--- /dev/null
+++ b/sysdeps/nacl/xstatconv.c
@@ -0,0 +1,76 @@
+/* Convert between the NaCl ABI's `struct stat' format, and libc's.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <sys/stat.h>
+#include <xstatconv.h>
+
+internal_function
+int
+__xstat_conv (int vers, const struct nacl_abi_stat *kbuf, void *ubuf)
+{
+  /* It's kosher enough just to crash here, but there are some
+     existing NaCl tests that like to see EFAULT, and that's what
+     making the IRT call with NULL would give.  */
+  if (__glibc_unlikely (ubuf == NULL))
+    {
+      __set_errno (EFAULT);
+      return -1;
+    }
+
+  switch (vers)
+    {
+    case _STAT_VER_NACL:
+      /* Nothing to do.  The struct is in the form the NaCl ABI expects.  */
+      *(struct nacl_abi_stat *) ubuf = *kbuf;
+      break;
+
+    case _STAT_VER_LINUX:
+      {
+        struct stat *buf = ubuf;
+
+        /* Zero-fill the pad/unused fields.  */
+        memset (buf, 0, sizeof *buf);
+
+        /* Convert from NaCl IRT ABI `struct stat'.  */
+        buf->st_dev = kbuf->nacl_abi_st_dev;
+        buf->st_ino = kbuf->nacl_abi_st_ino;
+        buf->st_mode = kbuf->nacl_abi_st_mode;
+        buf->st_nlink = kbuf->nacl_abi_st_nlink;
+        buf->st_uid = kbuf->nacl_abi_st_uid;
+        buf->st_gid = kbuf->nacl_abi_st_gid;
+        buf->st_rdev = kbuf->nacl_abi_st_rdev;
+        buf->st_size = kbuf->nacl_abi_st_size;
+        buf->st_blksize = kbuf->nacl_abi_st_blksize;
+        buf->st_blocks = kbuf->nacl_abi_st_blocks;
+        buf->st_atim.tv_sec = kbuf->nacl_abi_st_atime;
+        buf->st_atim.tv_nsec = kbuf->nacl_abi_st_atimensec;
+        buf->st_mtim.tv_sec = kbuf->nacl_abi_st_mtime;
+        buf->st_mtim.tv_nsec = kbuf->nacl_abi_st_mtimensec;
+        buf->st_ctim.tv_sec = kbuf->nacl_abi_st_ctime;
+        buf->st_ctim.tv_nsec = kbuf->nacl_abi_st_ctimensec;
+      }
+      break;
+
+    default:
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  return 0;
+}
diff --git a/sysdeps/nacl/xstatconv.h b/sysdeps/nacl/xstatconv.h
new file mode 100644
index 0000000000..fb313a2e62
--- /dev/null
+++ b/sysdeps/nacl/xstatconv.h
@@ -0,0 +1,32 @@
+/* Convert between the NaCl ABI's `struct stat' format, and libc's.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <nacl-interfaces.h>
+
+#define NACL_IN_TOOLCHAIN_HEADERS
+
+struct stat;
+
+/* stat.h uses nacl_abi_off_t, but irt.h defines only nacl_irt_off_t.  */
+typedef nacl_irt_off_t nacl_abi_off_t;
+
+/* We use this header to define struct nacl_abi_stat.  */
+#include <native_client/src/trusted/service_runtime/include/bits/stat.h>
+
+extern int __xstat_conv (int vers, const struct nacl_abi_stat *, void *)
+  internal_function attribute_hidden;