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[PATCH] Fix -D_FORTIFY_SOURCE=1 swprintf/vswprintf on ppc*/s390*/sparc*


Hi!

#include <wchar.h>
#include <stdio.h>

int
main (void)
{
  wchar_t buf[120], *buf2;
  swprintf (buf, 120, L"%La %La", 2.3L, 4.6L);
  printf ("%S\n", buf);
  asm ("" : "=r" (buf2) : "r" (buf));
  swprintf (buf2, 120, L"%La %La", 2.3L, 4.6L);
  printf ("%S\n", buf2);
  return 0;
}

built with -O2 -D_FORTIFY_SOURCE=1 -mlong-double-64 on ppc gives:
0x1.2666666666666p+1 0x1.2666666666666p+2
0x1.26666666666669333333333333p+1 0x0p+0
rather than the correct:
0x1.2666666666666p+1 0x1.2666666666666p+2
0x1.2666666666666p+1 0x1.2666666666666p+2
The problem is that when we use __{,v}swprintf_alias, it is redirected
to {,v}swprintf while we need __nldbl__{,v}swprintf.  Unfortunately,
as one redirection is already used, we can't fix this just in
bits/wchar-ldbl.h.  The following patch is IMHO still bearable.
{,v}s{,n}printf is ok, as we are using GCC builtins which will DTRT.
Unfortunately, there are no wide equivalent builtins.

2007-10-03  Jakub Jelinek  <jakub@redhat.com>

	* misc/sys/cdefs.h (__REDIRECT_LDBL, __REDIRECT_NTH_LDBL): New
	macros.
	* wcsmbs/bits/wchar2.h (__swprintf_alias, __vswprintf_alias): Use
	__REDIRECT_NTH_LDBL macro rather than __REDIRECT_NTH.

--- libc/misc/sys/cdefs.h.jj	2007-09-29 20:51:57.000000000 +0200
+++ libc/misc/sys/cdefs.h	2007-10-01 10:05:29.000000000 +0200
@@ -355,6 +360,10 @@
   extern __typeof (name) name __asm (__ASMNAME (#alias));
 #  define __LDBL_REDIR_DECL(name) \
   extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
+#  define __REDIRECT_LDBL(name, proto, alias) \
+  __LDBL_REDIR1 (name, proto, __nldbl_##alias)
+#  define __REDIRECT_NTH_LDBL(name, proto, alias) \
+  __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
 # endif
 #endif
 #if !defined __LDBL_COMPAT || !defined __REDIRECT
@@ -363,6 +372,11 @@
 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
 # define __LDBL_REDIR_DECL(name)
+# ifdef __REDIRECT
+#  define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
+#  define __REDIRECT_NTH_LDBL(name, proto, alias) \
+  __REDIRECT_NTH (name, proto, alias)
+# endif
 #endif
 
 #endif	 /* sys/cdefs.h */
--- libc/wcsmbs/bits/wchar2.h.jj	2007-09-29 20:51:58.000000000 +0200
+++ libc/wcsmbs/bits/wchar2.h	2007-10-01 10:07:22.000000000 +0200
@@ -274,10 +274,10 @@ extern int __swprintf_chk (wchar_t *__re
 			   __const wchar_t *__restrict __format, ...)
      __THROW /* __attribute__ ((__format__ (__wprintf__, 5, 6))) */;
 
-extern int __REDIRECT_NTH (__swprintf_alias,
-			   (wchar_t *__restrict __s, size_t __n,
-			    __const wchar_t *__restrict __fmt, ...),
-			    swprintf);
+extern int __REDIRECT_NTH_LDBL (__swprintf_alias,
+				(wchar_t *__restrict __s, size_t __n,
+				 __const wchar_t *__restrict __fmt, ...),
+				swprintf);
 
 #ifdef __va_arg_pack
 __extern_always_inline int
@@ -305,10 +305,10 @@ extern int __vswprintf_chk (wchar_t *__r
 			    __gnuc_va_list __arg)
      __THROW /* __attribute__ ((__format__ (__wprintf__, 5, 0))) */;
 
-extern int __REDIRECT_NTH (__vswprintf_alias,
-			   (wchar_t *__restrict __s, size_t __n,
-			    __const wchar_t *__restrict __fmt,
-			    __gnuc_va_list __ap), vswprintf);
+extern int __REDIRECT_NTH_LDBL (__vswprintf_alias,
+				(wchar_t *__restrict __s, size_t __n,
+				 __const wchar_t *__restrict __fmt,
+				 __gnuc_va_list __ap), vswprintf);
 
 __extern_always_inline int
 __NTH (vswprintf (wchar_t *__restrict __s, size_t __n,

	Jakub


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