Fix lgamma setting signgam for ISO C (bug 15421).

The lgamma (and likewise lgammaf, lgammal) function wrongly sets the
signgam variable even when building for strict ISO C conformance
(-std=c99 / -std=c11), although the user may define such a variable
and it's only in the implementation namespace for POSIX with XSI
extensions enabled.

Following discussions starting at
<https://sourceware.org/ml/libc-alpha/2013-04/msg00767.html> and
<https://sourceware.org/ml/libc-alpha/2015-10/msg00844.html>, it seems
that the safest approach for fixing this particular issue is for
signgam to become a weak alias for a newly exported symbol __signgam,
with the library functions only setting __signgam, at which point
static linker magic will preserve the alias for newly linked binaries
that refer to the library's signgam rather than defining their own,
while breaking the alias for programs that define their own signgam,
with new symbol versions for lgamma functions and with compat symbols
for existing binaries that set both signgam and __signgam.

This patch implements that approach for the fix.  signgam is made into
a weak alias.  The four symbols __signgam, lgamma, lgammaf, lgammal
get new symbol versions at version GLIBC_2.23, with the existing
versions of lgamma, lgammaf and lgammal becoming compat symbols.

When the compat versions are built, gamma, gammaf and gammal are
aliases for the compat versions (i.e. always set signgam); this is OK
as they are not ISO C functions, and avoids adding new symbol versions
for them unnecessarily.  When the compat versions are not built
(i.e. for static linking and for future glibc ports), gamma, gammaf
and gammal are aliases for the new versions that set __signgam.  The
ldbl-opt versions are updated accordingly.

The lgamma wrappers are adjusted so that the same source files,
included from different files with different definitions of
USE_AS_COMPAT, can build either the new versions or the compat
versions.  Similar changes are made to the ia64 versions (untested).

Tests are added that the lgamma functions do not interfere with a user
variable called signgam for ISO C, with various choices for the size
of that variable, whether it is initialized, and for static and
dynamic linking.  The conformtest whitelist entry is removed as well.

Tested for x86_64, x86, mips64 and powerpc, including looking at
objdump --dynamic-syms output to make sure the expected sets of
symbols were aliases.  Also spot-tested that a binary built with old
glibc works properly (i.e. gets signgam set) when run with new glibc.

	[BZ #15421]
	* sysdeps/ieee754/s_signgam.c (signgam): Rename to __signgam,
	initialize with 0 and define as weak alias of __signgam.
	* include/math.h [!_ISOMAC] (__signgam): Declare.
	* math/Makefile (libm-calls): Add w_lgamma_compat.
	(tests): Add test-signgam-uchar, test-signgam-uchar-init,
	test-signgam-uint, test-signgam-uint-init, test-signgam-ullong and
	test-signgam-ullong-init.
	(tests-static): Add test-signgam-uchar-static,
	test-signgam-uchar-init-static, test-signgam-uint-static,
	test-signgam-uint-init-static, test-signgam-ullong-static and
	test-signgam-ullong-init-static.
	(CFLAGS-test-signgam-uchar.c): New variable.
	(CFLAGS-test-signgam-uchar-init.c): Likewise.
	(CFLAGS-test-signgam-uchar-static.c): Likewise.
	(CFLAGS-test-signgam-uchar-init-static.c): Likewise.
	(CFLAGS-test-signgam-uint.c): Likewise.
	(CFLAGS-test-signgam-uint-init.c): Likewise.
	(CFLAGS-test-signgam-uint-static.c): Likewise.
	(CFLAGS-test-signgam-uint-init-static.c): Likewise.
	(CFLAGS-test-signgam-ullong.c): Likewise.
	(CFLAGS-test-signgam-ullong-init.c): Likewise.
	(CFLAGS-test-signgam-ullong-static.c): Likewise.
	(CFLAGS-test-signgam-ullong-init-static.c): Likewise.
	* math/Versions (libm): Add GLIBC_2.23.
	* math/lgamma-compat.h: New file.
	* math/test-signgam-main.c: Likewise.
	* math/test-signgam-uchar-init-static.c: Likewise.
	* math/test-signgam-uchar-init.c: Likewise.
	* math/test-signgam-uchar-static.c: Likewise.
	* math/test-signgam-uchar.c: Likewise.
	* math/test-signgam-uint-init-static.c: Likewise.
	* math/test-signgam-uint-init.c: Likewise.
	* math/test-signgam-uint-static.c: Likewise.
	* math/test-signgam-uint.c: Likewise.
	* math/test-signgam-ullong-init-static.c: Likewise.
	* math/test-signgam-ullong-init.c: Likewise.
	* math/test-signgam-ullong-static.c: Likewise.
	* math/test-signgam-ullong.c: Likewise.
	* math/w_lgamma.c: Rename to w_lgamma_main.c and replace by
	wrapper of w_lgamma_main.c.
	* math/w_lgamma_compat.c: New file.
	* math/w_lgamma_compatf.c: Likewise.
	* math/w_lgamma_compatl.c: Likewise.
	* math/w_lgamma_main.c: New file.  Based on w_lgamma.c.  Include
	<lgamma-compat.h>.  Condition contents on [BUILD_LGAMMA].  Support
	defining compatibility symbols.
	(__lgamma): Change to LGFUNC (__lgamma).  Use CALL_LGAMMA.
	* math/w_lgammaf.c: Rename to w_lgammaf_main.c and replace by
	wrapper of w_lgammaf_main.c.
	* math/w_lgammaf_main.c: New file.  Based on w_lgammaf.c.  Include
	<lgamma-compat.h>.  Condition contents on [BUILD_LGAMMA].  Support
	defining compatibility symbols.
	(__lgammaf): Change to LGFUNC (__lgammaf).  Use CALL_LGAMMA.
	* math/w_lgammal.c: Rename to w_lgammal_main.c and replace by
	wrapper of w_lgammal_main.c.
	* math/w_lgammal_main.c: New file.  Based on w_lgammal.c.  Include
	<lgamma-compat.h>.  Condition contents on [BUILD_LGAMMA].  Support
	defining compatibility symbols.
	(__lgammal): Change to LGFUNC (__lgammal).  Use CALL_LGAMMA.
	* sysdeps/ia64/fpu/lgamma-compat.h: New file.
	* sysdeps/ia64/fpu/w_lgamma.c: Move to ....
	* sysdeps/ia64/fpu/w_lgamma_main.c: ...here.  Include
	<lgamma-compat.h>.
	(__ieee754_lgamma): Change to LGFUNC (lgamma).  Use CALL_LGAMMA.
	(__ieee754_gamma): Define as alias.
	* sysdeps/ia64/fpu/w_lgammaf.c: Move to ....
	* sysdeps/ia64/fpu/w_lgammaf_main.c: ...here.  Include
	<lgamma-compat.h>.
	(__ieee754_lgammaf): Change to LGFUNC (lgammaf).  Use CALL_LGAMMA.
	(__ieee754_gammaf): Define as alias.
	* sysdeps/ia64/fpu/w_lgammal.c: Move to ....
	* sysdeps/ia64/fpu/w_lgammal_main.c: ...here.  Include
	<lgamma-compat.h>.
	(__ieee754_lgammal): Change to LGFUNC (lgammal).  Use CALL_LGAMMA.
	(__ieee754_gammal): Define as alias.
	* sysdeps/ieee754/ldbl-opt/w_lgamma.c: Move to ....
	* sysdeps/ieee754/ldbl-opt/w_lgamma_compat.c: ...here.  Include
	<math/w_lgamma_compat.c>.
	[LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)] (__lgammal_dbl_compat):
	Define as alias of __lgamma_compat and use in defining lgammal.
	* sysdeps/ieee754/ldbl-opt/w_lgammal.c: Move to ....
	* sysdeps/ieee754/ldbl-opt/w_lgamma_compatl.c: ...here.  Include
	<math/lgamma-compat.h> and <math/w_lgamma_compatl.c>.
	(USE_AS_COMPAT): New macro.
	(LGAMMA_OLD_VER): Undefine and redefine.
	(lgammal): Do not define here.
	(gammal): Only define here if [GAMMA_ALIAS].
	* conform/linknamespace.pl (@whitelist): Remove signgam.
	* sysdeps/nacl/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.

36 files changed, 225 insertions, 62 deletions

diff --git a/sysdeps/ia64/fpu/lgamma-compat.h b/sysdeps/ia64/fpu/lgamma-compat.h
new file mode 100644
index 0000000000..f9748393b7
--- /dev/null
+++ b/sysdeps/ia64/fpu/lgamma-compat.h
@@ -0,0 +1,42 @@
+/* ABI compatibility for lgamma functions.  ia64 version.
+   Copyright (C) 2015 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/>.  */
+
+#ifndef IA64_LGAMMA_COMPAT_H
+#define IA64_LGAMMA_COMPAT_H 1
+
+#include <math/lgamma-compat.h>
+
+#undef LGFUNC
+#if USE_AS_COMPAT
+# define LGFUNC(FUNC) __ ## FUNC ## _compat
+#else
+# define LGFUNC(FUNC) __ieee754_ ## FUNC
+#endif
+
+#undef CALL_LGAMMA
+#define CALL_LGAMMA(TYPE, FUNC, ARG)				\
+  ({								\
+    TYPE lgamma_tmp;						\
+    extern int __signgam, signgam;				\
+    lgamma_tmp = FUNC ((ARG), &__signgam, sizeof (__signgam));	\
+    if (USE_AS_COMPAT)						\
+      signgam = __signgam;					\
+    lgamma_tmp;							\
+  })
+
+#endif /* lgamma-compat.h.  */
diff --git a/sysdeps/ia64/fpu/w_lgamma.c b/sysdeps/ia64/fpu/w_lgamma_main.c
index 2006d3e806..6deffad987 100644
--- a/sysdeps/ia64/fpu/w_lgamma.c
+++ b/sysdeps/ia64/fpu/w_lgamma_main.c
@@ -53,28 +53,21 @@
 
 #include "libm_support.h"
 
+#include <lgamma-compat.h>
 
 extern double __libm_lgamma(double /*x*/, int* /*signgam*/, int /*signgamsz*/);
 
 
-double __ieee754_lgamma(double x)
+double LGFUNC (lgamma) (double x)
 {
-#ifdef __POSIX__
-    extern int    signgam;
-#else
-    int    signgam;
-#endif
-    return __libm_lgamma(x, &signgam, sizeof(signgam));
+    return CALL_LGAMMA (double, __libm_lgamma, x);
 }
-weak_alias (__ieee754_lgamma, lgamma)
-
-double __ieee754_gamma(double x)
-{
-#ifdef __POSIX__
-    extern int    signgam;
+#if USE_AS_COMPAT
+compat_symbol (libm, __lgammaf_compat, lgammaf, LGAMMA_OLD_VER);
 #else
-    int    signgam;
+versioned_symbol (libm, __ieee754_lgammaf, lgammaf, LGAMMA_NEW_VER);
+#endif
+#if GAMMA_ALIAS
+strong_alias (LGFUNC (lgammaf), __ieee754_gammaf)
+weak_alias (__ieee754_gammaf, gammaf)
 #endif
-    return __libm_lgamma(x, &signgam, sizeof(signgam));
-}
-weak_alias (__ieee754_gamma, gamma)
diff --git a/sysdeps/ia64/fpu/w_lgammaf.c b/sysdeps/ia64/fpu/w_lgammaf_main.c
index cd0b4f6666..d8e86a6f25 100644
--- a/sysdeps/ia64/fpu/w_lgammaf.c
+++ b/sysdeps/ia64/fpu/w_lgammaf_main.c
@@ -53,28 +53,21 @@
 
 #include "libm_support.h"
 
+#include <lgamma-compat.h>
 
 extern float  __libm_lgammaf(float /*x*/, int* /*signgam*/, int /*signgamsz*/);
 
 
-float __ieee754_lgammaf(float x)
+float LGFUNC (lgammaf) (float x)
 {
-#ifdef __POSIX__
-    extern int    signgam;
-#else
-    int    signgam;
-#endif
-    return __libm_lgammaf(x, &signgam, sizeof(signgam));
+    return CALL_LGAMMA (float, __libm_lgammaf, x);
 }
-weak_alias (__ieee754_lgammaf, lgammaf)
-
-float __ieee754_gammaf(float x)
-{
-#ifdef __POSIX__
-    extern int    signgam;
+#if USE_AS_COMPAT
+compat_symbol (libm, __lgammaf_compat, lgammaf, LGAMMA_OLD_VER);
 #else
-    int    signgam;
+versioned_symbol (libm, __ieee754_lgammaf, lgammaf, LGAMMA_NEW_VER);
 #endif
-    return __libm_lgammaf(x, &signgam, sizeof(signgam));
-}
+#if GAMMA_ALIAS
+strong_alias (LGFUNC (lgammaf), __ieee754_gammaf)
 weak_alias (__ieee754_gammaf, gammaf)
+#endif
diff --git a/sysdeps/ia64/fpu/w_lgammal.c b/sysdeps/ia64/fpu/w_lgammal_main.c
index e3885296eb..5c73f33430 100644
--- a/sysdeps/ia64/fpu/w_lgammal.c
+++ b/sysdeps/ia64/fpu/w_lgammal_main.c
@@ -55,25 +55,18 @@
 
 extern double __libm_lgammal(long double /*x*/, int* /*signgam*/, int /*signgamsz*/);
 
+#include <lgamma-compat.h>
 
-long double __ieee754_lgammal(long double x)
+long double LGFUNC (lgammal) (long double x)
 {
-#ifdef __POSIX__
-    extern int    signgam;
-#else
-    int    signgam;
-#endif
-    return __libm_lgammal(x, &signgam, sizeof(signgam));
+    return CALL_LGAMMA (long double, __libm_lgammal, x);
 }
-weak_alias (__ieee754_lgammal, lgammal)
-
-long double __ieee754_gammal(long double x)
-{
-#ifdef __POSIX__
-    extern int    signgam;
+#if USE_AS_COMPAT
+compat_symbol (libm, __lgammal_compat, lgammal, LGAMMA_OLD_VER);
 #else
-    int    signgam;
+versioned_symbol (libm, __ieee754_lgammal, lgammal, LGAMMA_NEW_VER);
 #endif
-    return __libm_lgammal(x, &signgam, sizeof(signgam));
-}
+#if GAMMA_ALIAS
+strong_alias (LGFUNC (lgammal), __ieee754_gammal)
 weak_alias (__ieee754_gammal, gammal)
+#endif
diff --git a/sysdeps/ieee754/ldbl-opt/w_lgamma.c b/sysdeps/ieee754/ldbl-opt/w_lgamma.c
deleted file mode 100644
index ef801c5505..0000000000
--- a/sysdeps/ieee754/ldbl-opt/w_lgamma.c
+++ /dev/null
@@ -1,6 +0,0 @@
-#include <math_ldbl_opt.h>
-#include <math/w_lgamma.c>
-#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
-compat_symbol (libm, __lgamma, lgammal, GLIBC_2_0);
-compat_symbol (libm, __gamma, gammal, GLIBC_2_0);
-#endif
diff --git a/sysdeps/ieee754/ldbl-opt/w_lgamma_compat.c b/sysdeps/ieee754/ldbl-opt/w_lgamma_compat.c
new file mode 100644
index 0000000000..f268e65a88
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/w_lgamma_compat.c
@@ -0,0 +1,7 @@
+#include <math_ldbl_opt.h>
+#include <math/w_lgamma_compat.c>
+#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
+strong_alias (__lgamma_compat, __lgammal_dbl_compat)
+compat_symbol (libm, __lgammal_dbl_compat, lgammal, GLIBC_2_0);
+compat_symbol (libm, __gamma, gammal, GLIBC_2_0);
+#endif
diff --git a/sysdeps/ieee754/ldbl-opt/w_lgamma_compatl.c b/sysdeps/ieee754/ldbl-opt/w_lgamma_compatl.c
new file mode 100644
index 0000000000..f60b3d7bcf
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/w_lgamma_compatl.c
@@ -0,0 +1,11 @@
+#include <math_ldbl_opt.h>
+#undef weak_alias
+#define weak_alias(n,a)
+#define USE_AS_COMPAT 1
+#include <math/lgamma-compat.h>
+#undef LGAMMA_OLD_VER
+#define LGAMMA_OLD_VER LONG_DOUBLE_COMPAT_VERSION
+#include <math/w_lgamma_compatl.c>
+#if GAMMA_ALIAS
+long_double_symbol (libm, __gammal, gammal);
+#endif
diff --git a/sysdeps/ieee754/ldbl-opt/w_lgammal.c b/sysdeps/ieee754/ldbl-opt/w_lgammal.c
deleted file mode 100644
index 9de7ec8f7f..0000000000
--- a/sysdeps/ieee754/ldbl-opt/w_lgammal.c
+++ /dev/null
@@ -1,6 +0,0 @@
-#include <math_ldbl_opt.h>
-#undef weak_alias
-#define weak_alias(n,a)
-#include <math/w_lgammal.c>
-long_double_symbol (libm, __lgammal, lgammal);
-long_double_symbol (libm, __gammal, gammal);
diff --git a/sysdeps/ieee754/s_signgam.c b/sysdeps/ieee754/s_signgam.c
index ee207d6505..9af3a75f1e 100644
--- a/sysdeps/ieee754/s_signgam.c
+++ b/sysdeps/ieee754/s_signgam.c
@@ -1,3 +1,4 @@
 #include <math.h>
 #include <math_private.h>
-int signgam;
+int __signgam = 0;
+weak_alias (__signgam, signgam)
diff --git a/sysdeps/nacl/libm.abilist b/sysdeps/nacl/libm.abilist
index d1fd77ab7f..055b0b25ba 100644
--- a/sysdeps/nacl/libm.abilist
+++ b/sysdeps/nacl/libm.abilist
@@ -367,3 +367,8 @@ GLIBC_2.22 y1l F
 GLIBC_2.22 yn F
 GLIBC_2.22 ynf F
 GLIBC_2.22 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/aarch64/libm.abilist b/sysdeps/unix/sysv/linux/aarch64/libm.abilist
index ead20e1c6d..2123113e25 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libm.abilist
@@ -398,3 +398,8 @@ GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
 GLIBC_2.18 __issignalingl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/alpha/libm.abilist b/sysdeps/unix/sysv/linux/alpha/libm.abilist
index 80838d3196..611dfe1aa5 100644
--- a/sysdeps/unix/sysv/linux/alpha/libm.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libm.abilist
@@ -408,6 +408,11 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.3.4 GLIBC_2.3.4 A
 GLIBC_2.3.4 __c1_cabsf F
 GLIBC_2.3.4 __c1_cacosf F
diff --git a/sysdeps/unix/sysv/linux/arm/libm.abilist b/sysdeps/unix/sysv/linux/arm/libm.abilist
index be96e9594b..e65e2309cd 100644
--- a/sysdeps/unix/sysv/linux/arm/libm.abilist
+++ b/sysdeps/unix/sysv/linux/arm/libm.abilist
@@ -56,6 +56,11 @@ GLIBC_2.15 __ynf_finite F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 _LIB_VERSION D 0x4
 GLIBC_2.4 __clog10 F
diff --git a/sysdeps/unix/sysv/linux/hppa/libm.abilist b/sysdeps/unix/sysv/linux/hppa/libm.abilist
index 3304e6ec8c..9b7f40a4c9 100644
--- a/sysdeps/unix/sysv/linux/hppa/libm.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libm.abilist
@@ -368,5 +368,10 @@ GLIBC_2.2 y1l F
 GLIBC_2.2 yn F
 GLIBC_2.2 ynf F
 GLIBC_2.2 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 exp2l F
diff --git a/sysdeps/unix/sysv/linux/i386/libm.abilist b/sysdeps/unix/sysv/linux/i386/libm.abilist
index e049a678cd..78b542e935 100644
--- a/sysdeps/unix/sysv/linux/i386/libm.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libm.abilist
@@ -410,4 +410,9 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/ia64/libm.abilist b/sysdeps/unix/sysv/linux/ia64/libm.abilist
index 39eafb8ab0..6d4cc72e0e 100644
--- a/sysdeps/unix/sysv/linux/ia64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libm.abilist
@@ -339,4 +339,9 @@ GLIBC_2.2 ynl F
 GLIBC_2.2.3 GLIBC_2.2.3 A
 GLIBC_2.2.3 matherrf F
 GLIBC_2.2.3 matherrl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
index be96e9594b..e65e2309cd 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
@@ -56,6 +56,11 @@ GLIBC_2.15 __ynf_finite F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 _LIB_VERSION D 0x4
 GLIBC_2.4 __clog10 F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
index 48ce23e978..2d31935916 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
@@ -408,4 +408,9 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/microblaze/libm.abilist b/sysdeps/unix/sysv/linux/microblaze/libm.abilist
index 15193f2039..149fd4f2be 100644
--- a/sysdeps/unix/sysv/linux/microblaze/libm.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/libm.abilist
@@ -367,3 +367,8 @@ GLIBC_2.18 y1l F
 GLIBC_2.18 yn F
 GLIBC_2.18 ynf F
 GLIBC_2.18 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist b/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
index b285c9b733..e599e82d6e 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
@@ -369,6 +369,11 @@ GLIBC_2.2 tgammal F
 GLIBC_2.2 trunc F
 GLIBC_2.2 truncf F
 GLIBC_2.2 truncl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 exp2l F
 _gp_disp _gp_disp A
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist b/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
index ff42af1f9e..164ba55263 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
@@ -400,4 +400,9 @@ GLIBC_2.2 tgammal F
 GLIBC_2.2 trunc F
 GLIBC_2.2 truncf F
 GLIBC_2.2 truncl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/nios2/libm.abilist b/sysdeps/unix/sysv/linux/nios2/libm.abilist
index dae4f5e4bd..ad02eff997 100644
--- a/sysdeps/unix/sysv/linux/nios2/libm.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libm.abilist
@@ -367,3 +367,8 @@ GLIBC_2.21 y1l F
 GLIBC_2.21 yn F
 GLIBC_2.21 ynf F
 GLIBC_2.21 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
index e18a51a5b7..5d2f263645 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
@@ -409,6 +409,11 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
index 90bfd19e7d..8b5edb52a0 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
@@ -408,6 +408,11 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
index df3457a70b..ee066837af 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
@@ -403,3 +403,8 @@ GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
 GLIBC_2.18 __issignalingl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
index ee01f69a12..6c7fc9b4fc 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
@@ -84,6 +84,11 @@ GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
 GLIBC_2.18 __issignalingl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.3 GLIBC_2.3 A
 GLIBC_2.3 _LIB_VERSION D 0x4
 GLIBC_2.3 __clog10 F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
index e14605bbe7..039ed5c521 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
@@ -398,6 +398,11 @@ GLIBC_2.2 GLIBC_2.2 A
 GLIBC_2.2 fedisableexcept F
 GLIBC_2.2 feenableexcept F
 GLIBC_2.2 fegetexcept F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
index b5abd132f9..66c625daeb 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
@@ -396,6 +396,11 @@ GLIBC_2.2 y1l F
 GLIBC_2.2 yn F
 GLIBC_2.2 ynf F
 GLIBC_2.2 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
diff --git a/sysdeps/unix/sysv/linux/sh/libm.abilist b/sysdeps/unix/sysv/linux/sh/libm.abilist
index 6fabd47dbb..93b84713d8 100644
--- a/sysdeps/unix/sysv/linux/sh/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sh/libm.abilist
@@ -368,5 +368,10 @@ GLIBC_2.2 y1l F
 GLIBC_2.2 yn F
 GLIBC_2.2 ynf F
 GLIBC_2.2 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 exp2l F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
index 2a5f5c7c91..d50ef4a920 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
@@ -400,6 +400,11 @@ GLIBC_2.2 feraiseexcept F
 GLIBC_2.2 fesetenv F
 GLIBC_2.2 fesetexceptflag F
 GLIBC_2.2 feupdateenv F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
index 80784c941a..b56add357b 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
@@ -399,4 +399,9 @@ GLIBC_2.2 y1l F
 GLIBC_2.2 yn F
 GLIBC_2.2 ynf F
 GLIBC_2.2 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
index df50da5464..18b8d00bec 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
@@ -368,3 +368,8 @@ GLIBC_2.15 __ynf_finite F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
index df50da5464..18b8d00bec 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
@@ -368,3 +368,8 @@ GLIBC_2.15 __ynf_finite F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
index df50da5464..18b8d00bec 100644
--- a/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
@@ -368,3 +368,8 @@ GLIBC_2.15 __ynf_finite F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
index a2cb7421f4..b911aff114 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
@@ -399,4 +399,9 @@ GLIBC_2.2.5 y1l F
 GLIBC_2.2.5 yn F
 GLIBC_2.2.5 ynf F
 GLIBC_2.2.5 ynl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F
 GLIBC_2.4 GLIBC_2.4 A
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
index 4d37717671..168c0d87cf 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
@@ -398,3 +398,8 @@ GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 __issignaling F
 GLIBC_2.18 __issignalingf F
 GLIBC_2.18 __issignalingl F
+GLIBC_2.23 GLIBC_2.23 A
+GLIBC_2.23 __signgam D 0x4
+GLIBC_2.23 lgamma F
+GLIBC_2.23 lgammaf F
+GLIBC_2.23 lgammal F