[COMMITTED] PowerPC: Fix memchr ifunc hidden symbol for PPC32

Message ID 537DF4F9.3080303@linux.vnet.ibm.com
State Committed

Commit Message

Adhemerval Zanella Netto May 22, 2014, 1 p.m. UTC
  This patch fixes a similar issue to
736c304a1ab4cee36a2f3343f1698bc0abae4608, where for PPC32 if the symbol
is defined as hidden (memchr) then compiler will create a local branc
(symbol@local) and the linker will not create a required PLT call to
make the ifunc work.  It changes the default hidden symbol (__GI_memchr)
to default memchr symbol for powerpc32 (__memchr_ppc32).

It fixes some segfaults due internal wrong calculation after memchr calls
in some iconv testcases.  I'm trying to figure out why it didn't have showed 
up earlier.


2014-05-22  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>

	* sysdeps/powerpc/powerpc32/power4/multiarch/memchr.c (memchr): Remove
	libc_hidden_builtin_def to ifunc.
	* sysdeps/powerpc/powerpc32/power4/multiarch/memchr-ppc32.c
	[libc_hidden_builtin_def]: Define hidden definition to __memchr_ppc32.



diff --git a/sysdeps/powerpc/powerpc32/power4/multiarch/memchr-ppc32.c b/sysdeps/powerpc/powerpc32/power4/multiarch/memchr-ppc32.c
index 4bd6bb9..f5db4a8 100644
--- a/sysdeps/powerpc/powerpc32/power4/multiarch/memchr-ppc32.c
+++ b/sysdeps/powerpc/powerpc32/power4/multiarch/memchr-ppc32.c
@@ -25,7 +25,8 @@ 
 #ifdef SHARED
 # undef libc_hidden_builtin_def
-# define libc_hidden_builtin_def(name)
+# define libc_hidden_builtin_def(name) \
+  __hidden_ver1(__memchr_ppc, __GI_memchr, __memchr_ppc);
 extern __typeof (memchr) __memchr_ppc attribute_hidden;
diff --git a/sysdeps/powerpc/powerpc32/power4/multiarch/memchr.c b/sysdeps/powerpc/powerpc32/power4/multiarch/memchr.c
index ca0f714..94c22ef 100644
--- a/sysdeps/powerpc/powerpc32/power4/multiarch/memchr.c
+++ b/sysdeps/powerpc/powerpc32/power4/multiarch/memchr.c
@@ -17,22 +17,25 @@ 
    <http://www.gnu.org/licenses/>.  */
 #ifndef NOT_IN_libc
+# undef memcpy
+/* Redefine memchr so that the compiler won't make the weak_alias point
+   to internal hidden definition (__GI_memchr), since PPC32 does not
+   support local IFUNC calls.  */
+# define memchr __redirect_memchr
 # include <string.h>
-# include <shlib-compat.h>
 # include "init-arch.h"
-extern __typeof (__memchr) __memchr_ppc attribute_hidden;
-extern __typeof (__memchr) __memchr_power7 attribute_hidden;
+extern __typeof (__redirect_memchr) __memchr_ppc attribute_hidden;
+extern __typeof (__redirect_memchr) __memchr_power7 attribute_hidden;
-/* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
-   ifunc symbol properly.  */
-libc_ifunc (__memchr,
+extern __typeof (__redirect_memchr) __libc_memchr;
+libc_ifunc (__libc_memchr,
 	    (hwcap & PPC_FEATURE_HAS_VSX)
             ? __memchr_power7
             : __memchr_ppc);
-weak_alias (__memchr, memchr)
-libc_hidden_builtin_def (memchr)
+#undef memchr
+weak_alias (__libc_memchr, memchr)
 #include <string/memchr.c>