glibc/sysdeps/i386/fpu/fegetenv.c
Joseph Myers 73a268c759 Fix libm fegetenv namespace (bug 17748).
Some C90 libm functions call fegetenv via libc_feholdsetround*
functions in math_private.h.  This patch makes them call __fegetenv
instead, making fegetenv into a weak alias for __fegetenv as needed.

Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).  Also tested for ARM
(soft-float) that fegetenv failures disappear from the linknamespace
test failures (however, similar fixes will also be needed for
fegetround, feholdexcept, fesetenv, fesetround and feupdateenv before
this set of namespace issues covered by bug 17748 is fully fixed and
those linknamespace tests start passing).

	[BZ #17748]
	* include/fenv.h (__fegetenv): Use libm_hidden_proto.
	* math/fegetenv.c (__fegetenv): Use libm_hidden_def.
	* sysdeps/aarch64/fpu/fegetenv.c (fegetenv): Rename to __fegetenv
	and define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/alpha/fpu/fegetenv.c (__fegetenv): Use libm_hidden_def.
	* sysdeps/arm/fegetenv.c (fegetenv): Rename to __fegetenv and
	define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/hppa/fpu/fegetenv.c (fegetenv): Likewise.
	* sysdeps/i386/fpu/fegetenv.c (__fegetenv): Use libm_hidden_def.
	* sysdeps/ia64/fpu/fegetenv.c (fegetenv): Rename to __fegetenv and
	define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/m68k/fpu/fegetenv.c (__fegetenv): Use libm_hidden_def.
	* sysdeps/mips/fpu/fegetenv.c (fegetenv): Rename to __fegetenv and
	define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/powerpc/fpu/fegetenv.c (__fegetenv): Use
	libm_hidden_def.
	* sysdeps/powerpc/nofpu/fegetenv.c (__fegetenv): Likewise.
	* sysdeps/powerpc/powerpc32/e500/nofpu/fegetenv.c (__fegetenv):
	Likewise.
	* sysdeps/s390/fpu/fegetenv.c (fegetenv): Rename to __fegetenv and
	define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/sh/sh4/fpu/fegetenv.c (fegetenv): Likewise.
	* sysdeps/sparc/fpu/fegetenv.c (__fegetenv): Use libm_hidden_def.
	* sysdeps/tile/math_private.h (__fegetenv): New inline function.
	* sysdeps/x86_64/fpu/fegetenv.c (fegetenv): Rename to __fegetenv
	and define as weak alias of __fegetenv.  Use libm_hidden_weak.
	* sysdeps/generic/math_private.h (libc_feholdsetround_ctx): Use
	__fegetenv instead of fegetenv.
	(libc_feholdsetround_noex_ctx): Likewise.
2014-12-31 22:07:52 +00:00

50 lines
1.7 KiB
C

/* Store current floating-point environment.
Copyright (C) 1997-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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 <fenv.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <dl-procinfo.h>
int
__fegetenv (fenv_t *envp)
{
__asm__ ("fnstenv %0" : "=m" (*envp));
/* And load it right back since the processor changes the mask.
Intel thought this opcode to be used in interrupt handlers which
would block all exceptions. */
__asm__ ("fldenv %0" : : "m" (*envp));
if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
__asm__ ("stmxcsr %0" : "=m" (envp->__eip));
/* Success. */
return 0;
}
#include <shlib-compat.h>
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
strong_alias (__fegetenv, __old_fegetenv)
compat_symbol (libm, __old_fegetenv, fegetenv, GLIBC_2_1);
#endif
libm_hidden_def (__fegetenv)
libm_hidden_ver (__fegetenv, fegetenv)
versioned_symbol (libm, __fegetenv, fegetenv, GLIBC_2_2);