Use gcc attribute ifunc in libc_ifunc macro instead of inline assembly due to false debuginfo.

The current s390 ifunc resolver for vector optimized functions and the common
libc_ifunc macro in include/libc-symbols.h uses something like that to generate ifunc'ed functions:
extern void *__resolve___strlen(unsigned long int dl_hwcap) asm (strlen);
asm (".type strlen, %gnu_indirect_function");

This leads to false debug information:
objdump --dwarf=info libc.so:
...
<1><1e6424>: Abbrev Number: 43 (DW_TAG_subprogram)
    <1e6425>   DW_AT_external    : 1
    <1e6425>   DW_AT_name        : (indirect string, offset: 0x1146e): __resolve___strlen
    <1e6429>   DW_AT_decl_file   : 1
    <1e642a>   DW_AT_decl_line   : 23
    <1e642b>   DW_AT_linkage_name: (indirect string, offset: 0x1147a): strlen
    <1e642f>   DW_AT_prototyped  : 1
    <1e642f>   DW_AT_type        : <0x1e4ccd>
    <1e6433>   DW_AT_low_pc      : 0x998e0
    <1e643b>   DW_AT_high_pc     : 0x16
    <1e6443>   DW_AT_frame_base  : 1 byte block: 9c     (DW_OP_call_frame_cfa)
    <1e6445>   DW_AT_GNU_all_call_sites: 1
    <1e6445>   DW_AT_sibling     : <0x1e6459>
 <2><1e6449>: Abbrev Number: 44 (DW_TAG_formal_parameter)
    <1e644a>   DW_AT_name        : (indirect string, offset: 0x1845): dl_hwcap
    <1e644e>   DW_AT_decl_file   : 1
    <1e644f>   DW_AT_decl_line   : 23
    <1e6450>   DW_AT_type        : <0x1e4c8d>
    <1e6454>   DW_AT_location    : 0x122115 (location list)
...

The debuginfo for the ifunc-resolver function contains the DW_AT_linkage_name
field, which names the real function name "strlen". If you perform an inferior
function call to strlen in lldb, then it fails due to something like that:
"error: no matching function for call to 'strlen'
candidate function not viable: no known conversion from 'const char [6]'
to 'unsigned long' for 1st argument"

The unsigned long is the dl_hwcap argument of the resolver function.
The strlen function itself has no debufinfo.

The s390 ifunc resolver for memset & co uses something like that:
asm (".globl FUNC"
     ".type FUNC, @gnu_indirect_function"
     ".set FUNC, __resolve_FUNC");

This way the debuginfo for the ifunc-resolver function does not conain the
DW_AT_linkage_name field and the real function has no debuginfo, too.

Using this strategy for the vector optimized functions leads to some troubles
for functions like strnlen. Here we have __strnlen and a weak alias strnlen.
The __strnlen function is the ifunc function, which is realized with the asm-
statement above. The weak_alias-macro can't be used here due to undefined symbol:
gcc ../sysdeps/s390/multiarch/strnlen.c -c ...
In file included from <command-line>:0:0:
../sysdeps/s390/multiarch/strnlen.c:28:24: error: ‘strnlen’ aliased to undefined symbol ‘__strnlen’
 weak_alias (__strnlen, strnlen)
                        ^
./../include/libc-symbols.h:111:26: note: in definition of macro ‘_weak_alias’
   extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
                          ^
../sysdeps/s390/multiarch/strnlen.c:28:1: note: in expansion of macro ‘weak_alias’
 weak_alias (__strnlen, strnlen)
 ^
make[2]: *** [build/string/strnlen.o] Error 1

As the __strnlen function is defined with asm-statements the function name
__strnlen isn't known by gcc. But the weak alias can also be done with an
asm statement to resolve this issue:
__asm__ (".weak  strnlen\n\t"
         ".set   strnlen,__strnlen\n");

In order to use the weak_alias macro, gcc needs to know the ifunc function. The
minimum gcc to build glibc is currently 4.7, which supports attribute((ifunc)).
See https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html.
It is only supported if gcc is configured with --enable-gnu-indirect-function
or gcc supports it by default for at least intel and s390x architecture.
This patch uses the old behaviour if gcc support is not available.
Usage of attribute ifunc is something like that:
__typeof (FUNC) FUNC __attribute__ ((ifunc ("__resolve_FUNC")));

Then gcc produces the same .globl, .type, .set assembler instructions like above.
And the debuginfo does not contain the DW_AT_linkage_name field and there is no
debuginfo for the real function, too.

But in order to get it work, there is also some extra work to do.
Currently, the glibc internal symbol on s390x e.g. __GI___strnlen is not the
ifunc symbol, but the fallback __strnlen_c symbol. Thus I have to omit the
libc_hidden_def macro in strnlen.c (here is the ifunc function __strnlen)
because it is already handled in strnlen-c.c (here is __strnlen_c).

Due to libc_hidden_proto (__strnlen) in string.h, compiling fails:
gcc ../sysdeps/s390/multiarch/strnlen.c -c ...
In file included from <command-line>:0:0:
../sysdeps/s390/multiarch/strnlen.c:53:24: error: ‘strnlen’ aliased to undefined symbol ‘__strnlen’
 weak_alias (__strnlen, strnlen)
                        ^
./../include/libc-symbols.h:111:26: note: in definition of macro ‘_weak_alias’
   extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
                          ^
../sysdeps/s390/multiarch/strnlen.c:53:1: note: in expansion of macro ‘weak_alias’
 weak_alias (__strnlen, strnlen)
 ^
make[2]: *** [build/string/strnlen.os] Error 1

I have to redirect the prototypes for __strnlen in string.h and create a copy
of the prototype for using as ifunc function:
__typeof (__redirect___strnlen) __strnlen __attribute__ ((ifunc ("__resolve_strnlen")));
weak_alias (__strnlen, strnlen)

This way there is no trouble with the internal __GI_* symbols.
Glibc builds fine with this construct and the debuginfo is "correct".
For functions without a __GI_* symbol like memccpy this redirection is not needed.

This patch adjusts the common libc_ifunc and libm_ifunc macro to use gcc
attribute ifunc. Due to this change, the macro users where the __GI_* symbol
does not target the ifunc symbol have to be prepared with the redirection
construct.
Furthermore a configure check to test gcc support is added. If it is not supported,
the old behaviour is used.

This patch also prepares the libc_ifunc macro to be useable in s390-ifunc-macro.
The s390 ifunc-resolver-functions do have an hwcaps parameter and not all
resolvers need the same initialization code. The next patch in this series
changes the s390 ifunc macros to use this common one.

ChangeLog:

	* include/libc-symbols.h (__ifunc_resolver):
	New macro is used by __ifunc* macros.
	(__ifunc): New macro uses gcc attribute ifunc or inline assembly
	depending on HAVE_GCC_IFUNC.
	(libc_ifunc, libm_ifunc): Use __ifunc as base macro.
	(libc_ifunc_redirected, libc_ifunc_hidden, libm_ifunc_init): New macro.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_finite.c:
	Redirect ifunced function in header for using as type for ifunc function.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_finitef.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isinf.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isinff.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isnan.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/memcmp.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/memcpy.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/memmove.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/mempcpy.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/memset.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/rawmemchr.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/strchr.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/strlen.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/strncmp.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/multiarch/strnlen.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_finite.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_finitef.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_isinf.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_isinff.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_isnan.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/memcmp.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/mempcpy.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/stpncpy.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strcat.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strchr.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strcmp.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strcpy.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strncmp.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strncpy.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strnlen.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strrchr.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/strstr.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/wcschr.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isnanf.c:
	Add libc_hidden_def() and use libc_ifunc_hidden() macro
	instead of libc_ifunc() macro.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_isnanf.c: Likewise.
	* sysdeps/powerpc/powerpc64/multiarch/stpcpy.c: Likewise.

15 files changed, 127 insertions, 85 deletions

diff --git a/sysdeps/powerpc/powerpc64/multiarch/memcmp.c b/sysdeps/powerpc/powerpc64/multiarch/memcmp.c
index e8cf6ae23d..a45ebd75a4 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/memcmp.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/memcmp.c
@@ -18,6 +18,7 @@
 
 /* Define multiple versions only for definition in libc.  */
 #if IS_IN (libc)
+# define memcmp __redirect_memcmp
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -25,15 +26,16 @@
 extern __typeof (memcmp) __memcmp_ppc attribute_hidden;
 extern __typeof (memcmp) __memcmp_power4 attribute_hidden;
 extern __typeof (memcmp) __memcmp_power7 attribute_hidden;
+# undef memcmp
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (memcmp,
-            (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __memcmp_power7 :
-	      (hwcap & PPC_FEATURE_POWER4)
-		? __memcmp_power4
-            : __memcmp_ppc);
+libc_ifunc_redirected (__redirect_memcmp, memcmp,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __memcmp_power7
+		       : (hwcap & PPC_FEATURE_POWER4)
+			 ? __memcmp_power4
+			 : __memcmp_ppc);
 #else
 #include <string/memcmp.c>
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/mempcpy.c b/sysdeps/powerpc/powerpc64/multiarch/mempcpy.c
index 3c77b5f1bd..36ec954e6f 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/mempcpy.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/mempcpy.c
@@ -17,23 +17,28 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define mempcpy __redirect_mempcpy
+# define __mempcpy __redirect___mempcpy
 # define NO_MEMPCPY_STPCPY_REDIRECT
+/* Omit the mempcpy inline definitions because it would redefine mempcpy.  */
+# define _HAVE_STRING_ARCH_mempcpy 1
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (__mempcpy) __mempcpy_ppc attribute_hidden;
 extern __typeof (__mempcpy) __mempcpy_power7 attribute_hidden;
+# undef mempcpy
+# undef __mempcpy
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (__mempcpy,
-	    (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __mempcpy_power7
-            : __mempcpy_ppc);
+libc_ifunc_redirected (__redirect___mempcpy, __mempcpy,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __mempcpy_power7
+		       : __mempcpy_ppc);
 
 weak_alias (__mempcpy, mempcpy)
-libc_hidden_def (mempcpy)
 #else
 # include <string/mempcpy.c>
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c b/sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c
index f06030eeeb..b53b148111 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c
@@ -17,19 +17,21 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define __rawmemchr __redirect___rawmemchr
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (__rawmemchr) __rawmemchr_ppc attribute_hidden;
 extern __typeof (__rawmemchr) __rawmemchr_power7 attribute_hidden;
+# undef __rawmemchr
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (__rawmemchr,
-	    (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __rawmemchr_power7
-            : __rawmemchr_ppc);
+libc_ifunc_redirected (__redirect___rawmemchr, __rawmemchr,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __rawmemchr_power7
+		       : __rawmemchr_ppc);
 
 weak_alias (__rawmemchr, rawmemchr)
 #else
diff --git a/sysdeps/powerpc/powerpc64/multiarch/stpcpy.c b/sysdeps/powerpc/powerpc64/multiarch/stpcpy.c
index bbc169180b..e378138379 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/stpcpy.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/stpcpy.c
@@ -26,14 +26,15 @@ extern __typeof (__stpcpy) __stpcpy_ppc attribute_hidden;
 extern __typeof (__stpcpy) __stpcpy_power7 attribute_hidden;
 extern __typeof (__stpcpy) __stpcpy_power8 attribute_hidden;
 
-libc_ifunc (__stpcpy,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __stpcpy_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __stpcpy_power7
-            : __stpcpy_ppc);
+libc_ifunc_hidden (__stpcpy, __stpcpy,
+		   (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		   ? __stpcpy_power8
+		   : (hwcap & PPC_FEATURE_HAS_VSX)
+		     ? __stpcpy_power7
+		     : __stpcpy_ppc);
 
 weak_alias (__stpcpy, stpcpy)
+libc_hidden_def (__stpcpy)
 libc_hidden_def (stpcpy)
 #else
 # include <string/stpcpy.c>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/stpncpy.c b/sysdeps/powerpc/powerpc64/multiarch/stpncpy.c
index b1484b1e36..fb3b529205 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/stpncpy.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/stpncpy.c
@@ -17,6 +17,8 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define stpncpy __redirect_stpncpy
+# define __stpncpy __redirect___stpncpy
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -24,13 +26,14 @@
 extern __typeof (__stpncpy) __stpncpy_ppc attribute_hidden;
 extern __typeof (__stpncpy) __stpncpy_power7 attribute_hidden;
 extern __typeof (__stpncpy) __stpncpy_power8 attribute_hidden;
+# undef stpncpy
+# undef __stpncpy
 
-libc_ifunc (__stpncpy,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __stpncpy_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __stpncpy_power7
-            : __stpncpy_ppc);
-
+libc_ifunc_redirected (__redirect___stpncpy, __stpncpy,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __stpncpy_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __stpncpy_power7
+			 : __stpncpy_ppc);
 weak_alias (__stpncpy, stpncpy)
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strcat.c b/sysdeps/powerpc/powerpc64/multiarch/strcat.c
index a2894ae027..5080ed1150 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strcat.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strcat.c
@@ -17,6 +17,7 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define strcat __redirect_strcat
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -24,11 +25,12 @@
 extern __typeof (strcat) __strcat_ppc attribute_hidden;
 extern __typeof (strcat) __strcat_power7 attribute_hidden;
 extern __typeof (strcat) __strcat_power8 attribute_hidden;
+# undef strcat
 
-libc_ifunc (strcat,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __strcat_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __strcat_power7
-            : __strcat_ppc);
+libc_ifunc_redirected (__redirect_strcat, strcat,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __strcat_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __strcat_power7
+			 : __strcat_ppc);
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchr.c b/sysdeps/powerpc/powerpc64/multiarch/strchr.c
index 2cfde632cb..e24d6b319e 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strchr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchr.c
@@ -18,18 +18,22 @@
 
 /* Define multiple versions only for definition in libc.  */
 #if defined SHARED && IS_IN (libc)
+# define strchr __redirect_strchr
+/* Omit the strchr inline definitions because it would redefine strchr.  */
+# define __NO_STRING_INLINES
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (strchr) __strchr_ppc attribute_hidden;
 extern __typeof (strchr) __strchr_power7 attribute_hidden;
+# undef strchr
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (strchr,
-	    (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __strchr_power7
-            : __strchr_ppc);
+libc_ifunc_redirected (__redirect_strchr, strchr,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __strchr_power7
+		       : __strchr_ppc);
 weak_alias (strchr, index)
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strcmp.c b/sysdeps/powerpc/powerpc64/multiarch/strcmp.c
index aee888a4b7..06f89cb375 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strcmp.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strcmp.c
@@ -17,6 +17,9 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if defined SHARED && IS_IN (libc)
+# define strcmp __redirect_strcmp
+/* Omit the strcmp inline definitions because it would redefine strcmp.  */
+# define __NO_STRING_INLINES
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -24,11 +27,12 @@
 extern __typeof (strcmp) __strcmp_ppc attribute_hidden;
 extern __typeof (strcmp) __strcmp_power7 attribute_hidden;
 extern __typeof (strcmp) __strcmp_power8 attribute_hidden;
+# undef strcmp
 
-libc_ifunc (strcmp,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-              ? __strcmp_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __strcmp_power7
-            : __strcmp_ppc);
+libc_ifunc_redirected (__redirect_strcmp, strcmp,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __strcmp_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __strcmp_power7
+			 : __strcmp_ppc);
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strcpy.c b/sysdeps/powerpc/powerpc64/multiarch/strcpy.c
index d2c38589e7..8708fc72ce 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strcpy.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strcpy.c
@@ -17,6 +17,7 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if defined SHARED && IS_IN (libc)
+# define strcpy __redirect_strcpy
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -24,11 +25,12 @@
 extern __typeof (strcpy) __strcpy_ppc attribute_hidden;
 extern __typeof (strcpy) __strcpy_power7 attribute_hidden;
 extern __typeof (strcpy) __strcpy_power8 attribute_hidden;
+#undef strcpy
 
-libc_ifunc (strcpy,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __strcpy_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __strcpy_power7
-            : __strcpy_ppc);
+libc_ifunc_redirected (__redirect_strcpy, strcpy,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __strcpy_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __strcpy_power7
+			 : __strcpy_ppc);
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncmp.c b/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
index 1eb6e517af..63a1aa049a 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
@@ -18,6 +18,9 @@
 
 /* Define multiple versions only for definition in libc.  */
 #if defined SHARED && IS_IN (libc)
+# define strncmp __redirect_strncmp
+/* Omit the strncmp inline definitions because it would redefine strncmp.  */
+# define __NO_STRING_INLINES
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -26,15 +29,16 @@ extern __typeof (strncmp) __strncmp_ppc attribute_hidden;
 extern __typeof (strncmp) __strncmp_power4 attribute_hidden;
 extern __typeof (strncmp) __strncmp_power7 attribute_hidden;
 extern __typeof (strncmp) __strncmp_power8 attribute_hidden;
+# undef strncmp
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (strncmp,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __strncmp_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __strncmp_power7 :
-		(hwcap & PPC_FEATURE_POWER4)
-		? __strncmp_power4
-            : __strncmp_ppc);
+libc_ifunc_redirected (__redirect_strncmp, strncmp,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __strncmp_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __strncmp_power7
+			 : (hwcap & PPC_FEATURE_POWER4)
+			   ? __strncmp_power4
+			   : __strncmp_ppc);
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncpy.c b/sysdeps/powerpc/powerpc64/multiarch/strncpy.c
index 0176514c1e..64495df4bc 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strncpy.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strncpy.c
@@ -18,6 +18,9 @@
 
 /* Define multiple versions only for definition in libc. */
 #if IS_IN (libc)
+# define strncpy __redirect_strncpy
+/* Omit the strncpy inline definitions because it would redefine strncpy.  */
+# define __NO_STRING_INLINES
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -25,14 +28,15 @@
 extern __typeof (strncpy) __strncpy_ppc attribute_hidden;
 extern __typeof (strncpy) __strncpy_power7 attribute_hidden;
 extern __typeof (strncpy) __strncpy_power8 attribute_hidden;
+# undef strncpy
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
  ifunc symbol properly. */
-libc_ifunc (strncpy,
-            (hwcap2 & PPC_FEATURE2_ARCH_2_07)
-            ? __strncpy_power8 :
-              (hwcap & PPC_FEATURE_HAS_VSX)
-              ? __strncpy_power7
-            : __strncpy_ppc);
+libc_ifunc_redirected (__redirect_strncpy, strncpy,
+		       (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+		       ? __strncpy_power8
+		       : (hwcap & PPC_FEATURE_HAS_VSX)
+			 ? __strncpy_power7
+			 : __strncpy_ppc);
 
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strnlen.c b/sysdeps/powerpc/powerpc64/multiarch/strnlen.c
index c4907e9ec8..71dc12dd9f 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strnlen.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strnlen.c
@@ -17,19 +17,21 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define strnlen __redirect_strnlen
+# define __strnlen __redirect___strnlen
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (__strnlen) __strnlen_ppc attribute_hidden;
 extern __typeof (__strnlen) __strnlen_power7 attribute_hidden;
-
-libc_ifunc (__strnlen,
-            (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __strnlen_power7
-            : __strnlen_ppc);
+# undef strnlen
+# undef __strnlen
+libc_ifunc_redirected (__redirect___strnlen, __strnlen,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __strnlen_power7
+		       : __strnlen_ppc);
 weak_alias (__strnlen, strnlen)
-libc_hidden_def (strnlen)
 
 #else
 #include <string/strnlen.c>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strrchr.c b/sysdeps/powerpc/powerpc64/multiarch/strrchr.c
index 45742bc910..e485b02248 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strrchr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strrchr.c
@@ -18,18 +18,20 @@
 
 /* Define multiple versions only for definition in libc.  */
 #if IS_IN (libc)
+# define strrchr __redirect_strrchr
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (strrchr) __strrchr_ppc attribute_hidden;
 extern __typeof (strrchr) __strrchr_power7 attribute_hidden;
+#undef strrchr
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (strrchr,
-            (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __strrchr_power7
-            : __strrchr_ppc);
+libc_ifunc_redirected (__redirect_strrchr, strrchr,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __strrchr_power7
+		       : __strrchr_ppc);
 weak_alias (strrchr, rindex)
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strstr.c b/sysdeps/powerpc/powerpc64/multiarch/strstr.c
index 7efc4b0913..9a390c2623 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strstr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strstr.c
@@ -18,17 +18,19 @@
 
 /* Define multiple versions only for definition in libc.  */
 #if IS_IN (libc)
+# define strstr __redirect_strstr
 # include <string.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
 
 extern __typeof (strstr) __strstr_ppc attribute_hidden;
 extern __typeof (strstr) __strstr_power7 attribute_hidden;
+# undef strstr
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (strstr,
-            (hwcap & PPC_FEATURE_HAS_VSX)
-            ? __strstr_power7
-            : __strstr_ppc);
+libc_ifunc_redirected (__redirect_strstr, strstr,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __strstr_power7
+		       : __strstr_ppc);
 #endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/wcschr.c b/sysdeps/powerpc/powerpc64/multiarch/wcschr.c
index 44c9b971ce..a4705423b0 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/wcschr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/wcschr.c
@@ -17,6 +17,8 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define wcschr __redirect_wcschr
+# define __wcschr __redirect___wcschr
 # include <wchar.h>
 # include <shlib-compat.h>
 # include "init-arch.h"
@@ -24,15 +26,16 @@
 extern __typeof (wcschr) __wcschr_ppc attribute_hidden;
 extern __typeof (wcschr) __wcschr_power6 attribute_hidden;
 extern __typeof (wcschr) __wcschr_power7 attribute_hidden;
+# undef wcschr
+# undef __wcschr
 
-libc_ifunc (__wcschr,
-	     (hwcap & PPC_FEATURE_HAS_VSX)
-             ? __wcschr_power7 :
-	       (hwcap & PPC_FEATURE_ARCH_2_05)
-	       ? __wcschr_power6
-             : __wcschr_ppc);
+libc_ifunc_redirected (__redirect___wcschr, __wcschr,
+		       (hwcap & PPC_FEATURE_HAS_VSX)
+		       ? __wcschr_power7
+		       : (hwcap & PPC_FEATURE_ARCH_2_05)
+			 ? __wcschr_power6
+			 : __wcschr_ppc);
 weak_alias (__wcschr, wcschr)
-libc_hidden_builtin_def (wcschr)
 #else
 #undef libc_hidden_def
 #define libc_hidden_def(a)