From 9967e003b32d20441892386f1092d1aded51e1aa Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Tue, 12 Mar 2013 12:47:36 -0700 Subject: Add sysdeps/init_array to produce empty crt[in].o and use .preinit_array for gcrt1.o --- ChangeLog | 13 +++++++++++++ csu/elf-init.c | 7 +++++++ csu/gmon-start.c | 7 +++++++ sysdeps/init_array/crti.S | 13 +++++++++++++ sysdeps/init_array/crtn.S | 13 +++++++++++++ sysdeps/init_array/elf-init.c | 37 +++++++++++++++++++++++++++++++++++++ sysdeps/init_array/gmon-start.c | 41 +++++++++++++++++++++++++++++++++++++++++ 7 files changed, 131 insertions(+) create mode 100644 sysdeps/init_array/crti.S create mode 100644 sysdeps/init_array/crtn.S create mode 100644 sysdeps/init_array/elf-init.c create mode 100644 sysdeps/init_array/gmon-start.c diff --git a/ChangeLog b/ChangeLog index db68e8a5f9..2019234c1a 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2013-03-12 Roland McGrath + + * sysdeps/init_array/elf-init.c: New file. + * csu/elf-init.c + (__libc_csu_init) [!NO_INITFINI]: Conditionalize _init call on this. + (__libc_csu_fini) [!NO_INITFINI]: Conditionalize _fini call on this. + + * csu/gmon-start.c [GMON_START_ARRAY_SECTION]: Don't define + __gmon_start__ as global, but as static with a .preinit_array pointer. + * sysdeps/init_array/gmon-start.c: New file. Use that. + * sysdeps/init_array/crti.S: New file, empty except for comments. + * sysdeps/init_array/crtn.S: Likewise. + 2013-03-11 Ondřej Bílka * sysdeps/x86_64/memset.S: Remove USE_MULTIARCH conditional for diff --git a/csu/elf-init.c b/csu/elf-init.c index 1e231c1a08..84700e6fff 100644 --- a/csu/elf-init.c +++ b/csu/elf-init.c @@ -49,10 +49,13 @@ extern void (*__fini_array_start []) (void) attribute_hidden; extern void (*__fini_array_end []) (void) attribute_hidden; +#ifndef NO_INITFINI /* These function symbols are provided for the .init/.fini section entry points automagically by the linker. */ extern void _init (void); extern void _fini (void); +#endif + /* These functions are passed to __libc_start_main by the startup code. These get statically linked into each program. For dynamically linked @@ -76,7 +79,9 @@ __libc_csu_init (int argc, char **argv, char **envp) } #endif +#ifndef NO_INITFINI _init (); +#endif const size_t size = __init_array_end - __init_array_start; for (size_t i = 0; i < size; i++) @@ -94,6 +99,8 @@ __libc_csu_fini (void) while (i-- > 0) (*__fini_array_start [i]) (); +# ifndef NO_INITFINI _fini (); +# endif #endif } diff --git a/csu/gmon-start.c b/csu/gmon-start.c index 54495eb493..0c18321095 100644 --- a/csu/gmon-start.c +++ b/csu/gmon-start.c @@ -59,10 +59,17 @@ extern char etext[]; # endif #endif +#ifdef GMON_START_ARRAY_SECTION +static void __gmon_start__ (void); +static void (*const gmon_start_initializer) (void) + __attribute__ ((used, section (GMON_START_ARRAY_SECTION))) = &__gmon_start__; +static +#else /* We cannot use the normal constructor mechanism to call __gmon_start__ because gcrt1.o appears before crtbegin.o in the link. Instead crti.o calls it specially. */ extern void __gmon_start__ (void); +#endif void __gmon_start__ (void) diff --git a/sysdeps/init_array/crti.S b/sysdeps/init_array/crti.S new file mode 100644 index 0000000000..0a6e9fd953 --- /dev/null +++ b/sysdeps/init_array/crti.S @@ -0,0 +1,13 @@ +/* Dummy crti file. + + In this configuration, crti.o and crtn.o are both empty because the + .init_array/.fini_array sections are used exclusively. + + Older ports cannot use this because even if the linker used to + build libc itself has .init_array support, we don't want to produce + a crt[in].o that presume a linker that new will be used to link + other things later. + + But new configurations without compatibility concerns for + toolchains without .init_array support can use this to avoid the + superfluous .init and .fini boilerplate code. */ diff --git a/sysdeps/init_array/crtn.S b/sysdeps/init_array/crtn.S new file mode 100644 index 0000000000..6f70e77160 --- /dev/null +++ b/sysdeps/init_array/crtn.S @@ -0,0 +1,13 @@ +/* Dummy crtn file. + + In this configuration, crti.o and crtn.o are both empty because the + .init_array/.fini_array sections are used exclusively. + + Older ports cannot use this because even if the linker used to + build libc itself has .init_array support, we don't want to produce + a crt[in].o that presume a linker that new will be used to link + other things later. + + But new configurations without compatibility concerns for + toolchains without .init_array support can use this to avoid the + superfluous .init and .fini boilerplate code. */ diff --git a/sysdeps/init_array/elf-init.c b/sysdeps/init_array/elf-init.c new file mode 100644 index 0000000000..c6467aac87 --- /dev/null +++ b/sysdeps/init_array/elf-init.c @@ -0,0 +1,37 @@ +/* Startup support for ELF initializers/finalizers in the main executable. + Copyright (C) 2013 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 + . */ + +#define NO_INITFINI +#include diff --git a/sysdeps/init_array/gmon-start.c b/sysdeps/init_array/gmon-start.c new file mode 100644 index 0000000000..6f2d6dc8b9 --- /dev/null +++ b/sysdeps/init_array/gmon-start.c @@ -0,0 +1,41 @@ +/* gmon startup hook using .preinit_array. + Copyright (C) 2013 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 + . */ + +/* Instead of defining __gmon_start__ globally in gcrt1.o, we make it + static and just put a pointer to it into the .preinit_array section. */ + +#define GMON_START_ARRAY_SECTION ".preinit_array" + +#include -- cgit 1.4.1