glibc/nptl/pt-system.c
Andreas Schwab fc5ad7024c Don't use IFUNC resolver for longjmp or system in libpthread (bug 21041)
Unlike the vfork forwarder and like the fork forwarder as in bug 19861,
there won't be a problem when the compiler does not turn this into a tail
call.
2017-08-08 17:01:25 +02:00

46 lines
1.8 KiB
C

/* ABI compatibility for 'system' symbol in libpthread ABI.
Copyright (C) 2002-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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 <stdlib.h>
#include <shlib-compat.h>
/* libpthread once had its own 'system', though there was no apparent
reason for it. There is no use in having a separate symbol in
libpthread, but the historical ABI requires it. For static linking,
there is no need to provide anything here--the libc version will be
linked in. For shared library ABI compatibility, there must be a
'system' symbol in libpthread.so.
With an IFUNC resolver, it would be possible to avoid the indirection,
but the IFUNC resolver might run before the __libc_system symbol has
been relocated, in which case the IFUNC resolver would not be able to
provide the correct address. */
#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_22)
static int __attribute__ ((used))
system_compat (const char *line)
{
return __libc_system (line);
}
strong_alias (system_compat, system_alias)
compat_symbol (libpthread, system_alias, system, GLIBC_2_0);
#endif