mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-10 07:10:06 +00:00
505c884aeb
If libc_hidden_builtin_{def,proto} isn't properly set for *_chk routines,
there are unwanted PLT entries in libc.so.
There is a special case with __asprintf_chk:
If ldbl_* macros are used for asprintf, ABI gets broken on s390x,
if it isn't, ppc64le isn't building due to multiple asm redirections.
This is due to the inclusion of bits/stdio-lbdl.h for ppc64le whereas it
isn't for s390x. This header creates redirections, which are not
compatible with the ones generated using libc_hidden_def.
Yet, we can't use libc_hidden_ldbl_proto on s390x since it will not
create a simple strong alias (e.g. as done on x86_64), but a versioned
alias, leading to ABI breakage.
This results in errors on s390x:
/usr/bin/ld: glibc/iconv/../libio/bits/stdio2.h:137: undefined reference
to `__asprintf_chk'
Original __asprintf_chk symbols:
00000000001395b0 T __asprintf_chk
0000000000177e90 T __nldbl___asprintf_chk
__asprintf_chk symbols with ldbl_* macros:
000000000012d590 t ___asprintf_chk
000000000012d590 t __asprintf_chk@@GLIBC_2.4
000000000012d590 t __GI___asprintf_chk
000000000012d590 t __GL____asprintf_chk___asprintf_chk
0000000000172240 T __nldbl___asprintf_chk
__asprintf_chk symbols with the patch:
000000000012d590 t ___asprintf_chk
000000000012d590 T __asprintf_chk
000000000012d590 t __GI___asprintf_chk
0000000000172240 T __nldbl___asprintf_chk
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
55 lines
2.0 KiB
C
55 lines
2.0 KiB
C
/* Copyright (C) 1991-2023 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <stdarg.h>
|
|
#include <libio/libioP.h>
|
|
|
|
|
|
/* Write formatted output from FORMAT to a string which is
|
|
allocated with malloc and stored in *STRING_PTR. */
|
|
int
|
|
___asprintf_chk (char **result_ptr, int flag, const char *format, ...)
|
|
{
|
|
/* For flag > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
|
|
can only come from read-only format strings. */
|
|
unsigned int mode = (flag > 0) ? PRINTF_FORTIFY : 0;
|
|
va_list ap;
|
|
int ret;
|
|
|
|
va_start (ap, format);
|
|
ret = __vasprintf_internal (result_ptr, format, ap, mode);
|
|
va_end (ap);
|
|
|
|
return ret;
|
|
}
|
|
#if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
|
|
/* This is needed since <bits/stdio-lbdl.h> is included in this case, leading to
|
|
* multiple asm redirection of the same symbol
|
|
*/
|
|
ldbl_hidden_def (___asprintf_chk, __asprintf_chk)
|
|
ldbl_strong_alias (___asprintf_chk, __asprintf_chk)
|
|
#else
|
|
/* On some systems introduction of ldbl_* macros lead to ABI breakage due to the
|
|
* long_double_symbol aliasing, e.g. on s390x:
|
|
* /usr/bin/ld: glibc/iconv/../libio/bits/stdio2.h:137: undefined reference to
|
|
* `__asprintf_chk'
|
|
* Due to __asprintf_chk@@GLIBC_2.4 alias replacing __asprintf_chk.
|
|
*/
|
|
strong_alias (___asprintf_chk, __asprintf_chk)
|
|
libc_hidden_def (__asprintf_chk)
|
|
#endif
|