Fix swscanf vswscanf namespace (bug 18542).

swscanf (added in C90 Amendment 1, present in UNIX98) calls vswscanf
(added in C99, not in C90 Amendment 1 or UNIX98).  This patch fixes
this by using __vswscanf instead and making vswscanf into a weak
alias.

(I intend to add conform/ test support for C90 Amendment 1 - and
various other standard versions supported by glibc but not yet by
conform/ tests - at some point, once the results for currently tested
standards are cleaner.)

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	[BZ #18542]
	* libio/iovswscanf.c (__vswscanf): Use libc_hidden_def.
	(vswscanf): Use ldbl_weak_alias instead of ldbl_strong_alias
	* include/wchar.h (__vswscanf): Declare.  Use libc_hidden_proto.
	* libio/swscanf.c (__swscanf): Call __vswscanf instead of
	vswscanf.
	* conform/Makefile (test-xfail-UNIX98/wchar.h/linknamespace):
	Remove variable.

ChangeLog

@@ -1,5 +1,14 @@
 2015-06-17  Joseph Myers  <joseph@codesourcery.com>
 
+	[BZ #18542]
+	* libio/iovswscanf.c (__vswscanf): Use libc_hidden_def.
+	(vswscanf): Use ldbl_weak_alias instead of ldbl_strong_alias
+	* include/wchar.h (__vswscanf): Declare.  Use libc_hidden_proto.
+	* libio/swscanf.c (__swscanf): Call __vswscanf instead of
+	vswscanf.
+	* conform/Makefile (test-xfail-UNIX98/wchar.h/linknamespace):
+	Remove variable.
+
 	[BZ #18540]
 	* libio/iofflush.c [!_IO_MTSAFE_IO] (__fflush_unlocked): Define as
 	strong alias of _IO_fflush.  Use libc_hidden_def.

NEWS

@@ -22,7 +22,7 @@ Version 2.22
   18324, 18333, 18346, 18397, 18409, 18410, 18412, 18418, 18422, 18434,
   18444, 18468, 18469, 18470, 18479, 18483, 18495, 18496, 18497, 18498,
   18507, 18512, 18519, 18520, 18522, 18527, 18528, 18529, 18530, 18532,
-  18533, 18534, 18536, 18539, 18540.
+  18533, 18534, 18536, 18539, 18540, 18542.
 
 * Cache information can be queried via sysconf() function on s390 e.g. with
   _SC_LEVEL1_ICACHE_SIZE as argument.

conform/Makefile

@@ -348,4 +348,3 @@ test-xfail-XPG3/unistd.h/linknamespace = yes
 test-xfail-XPG4/unistd.h/linknamespace = yes
 test-xfail-POSIX/mqueue.h/linknamespace = yes
 test-xfail-UNIX98/mqueue.h/linknamespace = yes
-test-xfail-UNIX98/wchar.h/linknamespace = yes

include/wchar.h

@@ -197,7 +197,11 @@ extern int __isoc99_vwscanf (const wchar_t *__restrict __format,
 extern int __isoc99_vswscanf (const wchar_t *__restrict __s,
 			      const wchar_t *__restrict __format,
 			      __gnuc_va_list __arg) __THROW;
+extern int __vswscanf (const wchar_t *__restrict __s,
+		       const wchar_t *__restrict __format,
+		       __gnuc_va_list __arg) __THROW;
 libc_hidden_proto (__isoc99_vswscanf)
+libc_hidden_proto (__vswscanf)
 libc_hidden_proto (__isoc99_vfwscanf)
 
 /* Internal functions.  */

libio/iovswscanf.c

@@ -43,5 +43,6 @@ __vswscanf (const wchar_t *string, const wchar_t *format, _IO_va_list args)
   ret = _IO_vfwscanf ((_IO_FILE *) &sf._sbf, format, args, NULL);
   return ret;
 }
+libc_hidden_def (__vswscanf)
 ldbl_hidden_def (__vswscanf, vswscanf)
-ldbl_strong_alias (__vswscanf, vswscanf)
+ldbl_weak_alias (__vswscanf, vswscanf)

libio/swscanf.c

@@ -28,7 +28,7 @@ __swscanf (const wchar_t *s, const wchar_t *format, ...)
   int done;
 
   va_start (arg, format);
-  done = vswscanf (s, format, arg);
+  done = __vswscanf (s, format, arg);
   va_end (arg);
 
   return done;