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-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/x86_64/vfork.S55
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diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/vfork.S b/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/vfork.S
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index 0000000000..a8b0369fb3
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/vfork.S
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+/* Copyright (C) 2001-2017 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>
+#define _ERRNO_H	1
+#include <bits/errno.h>
+#include <tcb-offsets.h>
+
+
+/* Clone the calling process, but without copying the whole address space.
+   The calling process is suspended until the new process exits or is
+   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
+   and the process ID of the new process to the old process.  */
+
+ENTRY (__vfork)
+
+	/* Pop the return PC value into RDI.  We need a register that
+	   is preserved by the syscall and that we're allowed to destroy. */
+	popq	%rdi
+	cfi_adjust_cfa_offset(-8)
+	cfi_register(%rip, %rdi)
+
+	/* Stuff the syscall number in RAX and enter into the kernel.  */
+	movl	$SYS_ify (vfork), %eax
+	syscall
+
+	/* Push back the return PC.  */
+	pushq	%rdi
+	cfi_adjust_cfa_offset(8)
+
+	cmpl	$-4095, %eax
+	jae SYSCALL_ERROR_LABEL		/* Branch forward if it failed.  */
+
+	/* Normal return.  */
+	ret
+
+PSEUDO_END (__vfork)
+libc_hidden_def (__vfork)
+
+weak_alias (__vfork, vfork)
+strong_alias (__vfork, __libc_vfork)