commit 2a44960cbc78713c6a2721683a4319d50e71a01f

Author: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date:   Thu Jul 7 18:12:58 2022 -0300

    Apply asm redirections in stdio.h before first use [BZ #27087]

    Compilers may not be able to apply asm redirections to functions after

    these functions are used for the first time, e.g. clang 13.

    Fix [BZ #27087] by applying all long double-related asm redirections

    before using functions in bits/stdio.h.

    However, as these asm redirections depend on the declarations provided

    by libio/bits/stdio2.h, this header was split in 2:

     - libio/bits/stdio2-decl.h contains all function declarations;

     - libio/bits/stdio2.h remains with the remaining contents, including

       redirections.

    This also adds the access attribute to __vsnprintf_chk that was missing.

    Tested with build-many-glibcs.py.

    Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>

    (cherry picked from commit d0fa09a7701956036ff36f8ca188e9fff81553d8)

diff --git a/include/bits/stdio2-decl.h b/include/bits/stdio2-decl.h

new file mode 100644

index 0000000000000000..bbb052f192218219

--- /dev/null

+++ b/include/bits/stdio2-decl.h

@@ -0,0 +1 @@

+#include <libio/bits/stdio2-decl.h>

diff --git a/libio/Makefile b/libio/Makefile

index 5336b7d59584927f..981c876940f67fbf 100644

--- a/libio/Makefile

+++ b/libio/Makefile

@@ -23,7 +23,7 @@ subdir	:= libio

 include ../Makeconfig

 headers	:= stdio.h \

-	   bits/stdio.h bits/stdio2.h bits/stdio-ldbl.h \

+	   bits/stdio.h bits/stdio2.h bits/stdio2-decl.h bits/stdio-ldbl.h \

 	   bits/types/FILE.h bits/types/__FILE.h bits/types/struct_FILE.h \

 	   bits/types/__fpos_t.h bits/types/__fpos64_t.h \

 	   bits/types/cookie_io_functions_t.h

diff --git a/libio/bits/stdio2-decl.h b/libio/bits/stdio2-decl.h

new file mode 100644

index 0000000000000000..e398f7182b98e4d7

--- /dev/null

+++ b/libio/bits/stdio2-decl.h

@@ -0,0 +1,111 @@

+/* Checking macros for stdio functions. Declarations only.

+   Copyright (C) 2004-2022 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

+   <https://www.gnu.org/licenses/>.  */

+

+#ifndef _BITS_STDIO2_DEC_H

+#define _BITS_STDIO2_DEC_H 1

+

+#ifndef _STDIO_H

+# error "Never include <bits/stdio2-decl.h> directly; use <stdio.h> instead."

+#endif

+

+extern int __sprintf_chk (char *__restrict __s, int __flag, size_t __slen,

+			  const char *__restrict __format, ...) __THROW

+    __attr_access ((__write_only__, 1, 3));

+extern int __vsprintf_chk (char *__restrict __s, int __flag, size_t __slen,

+			   const char *__restrict __format,

+			   __gnuc_va_list __ap) __THROW

+    __attr_access ((__write_only__, 1, 3));

+

+#if defined __USE_ISOC99 || defined __USE_UNIX98

+

+extern int __snprintf_chk (char *__restrict __s, size_t __n, int __flag,

+			   size_t __slen, const char *__restrict __format,

+			   ...) __THROW

+    __attr_access ((__write_only__, 1, 2));

+extern int __vsnprintf_chk (char *__restrict __s, size_t __n, int __flag,

+			    size_t __slen, const char *__restrict __format,

+			    __gnuc_va_list __ap) __THROW

+    __attr_access ((__write_only__, 1, 2));

+

+#endif

+

+#if __USE_FORTIFY_LEVEL > 1

+

+extern int __fprintf_chk (FILE *__restrict __stream, int __flag,

+			  const char *__restrict __format, ...);

+extern int __printf_chk (int __flag, const char *__restrict __format, ...);

+extern int __vfprintf_chk (FILE *__restrict __stream, int __flag,

+			   const char *__restrict __format, __gnuc_va_list __ap);

+extern int __vprintf_chk (int __flag, const char *__restrict __format,

+			  __gnuc_va_list __ap);

+

+# ifdef __USE_XOPEN2K8

+extern int __dprintf_chk (int __fd, int __flag, const char *__restrict __fmt,

+			  ...) __attribute__ ((__format__ (__printf__, 3, 4)));

+extern int __vdprintf_chk (int __fd, int __flag,

+			   const char *__restrict __fmt, __gnuc_va_list __arg)

+     __attribute__ ((__format__ (__printf__, 3, 0)));

+# endif

+

+# ifdef __USE_GNU

+

+extern int __asprintf_chk (char **__restrict __ptr, int __flag,

+			   const char *__restrict __fmt, ...)

+     __THROW __attribute__ ((__format__ (__printf__, 3, 4))) __wur;

+extern int __vasprintf_chk (char **__restrict __ptr, int __flag,

+			    const char *__restrict __fmt, __gnuc_va_list __arg)

+     __THROW __attribute__ ((__format__ (__printf__, 3, 0))) __wur;

+extern int __obstack_printf_chk (struct obstack *__restrict __obstack,

+				 int __flag, const char *__restrict __format,

+				 ...)

+     __THROW __attribute__ ((__format__ (__printf__, 3, 4)));

+extern int __obstack_vprintf_chk (struct obstack *__restrict __obstack,

+				  int __flag,

+				  const char *__restrict __format,

+				  __gnuc_va_list __args)

+     __THROW __attribute__ ((__format__ (__printf__, 3, 0)));

+

+# endif

+#endif

+

+#if __GLIBC_USE (DEPRECATED_GETS)

+extern char *__gets_chk (char *__str, size_t) __wur;

+#endif

+

+extern char *__fgets_chk (char *__restrict __s, size_t __size, int __n,

+			  FILE *__restrict __stream)

+    __wur __attr_access ((__write_only__, 1, 3));

+

+extern size_t __fread_chk (void *__restrict __ptr, size_t __ptrlen,

+			   size_t __size, size_t __n,

+			   FILE *__restrict __stream) __wur;

+

+#ifdef __USE_GNU

+extern char *__fgets_unlocked_chk (char *__restrict __s, size_t __size,

+				   int __n, FILE *__restrict __stream)

+    __wur __attr_access ((__write_only__, 1, 3));

+#endif

+

+#ifdef __USE_MISC

+# undef fread_unlocked

+extern size_t __fread_unlocked_chk (void *__restrict __ptr, size_t __ptrlen,

+				    size_t __size, size_t __n,

+				    FILE *__restrict __stream) __wur;

+#endif

+

+#endif /* bits/stdio2-decl.h.  */

diff --git a/libio/bits/stdio2.h b/libio/bits/stdio2.h

index 40ff16b01b4f4876..4570f86a4496c1ee 100644

--- a/libio/bits/stdio2.h

+++ b/libio/bits/stdio2.h

@@ -23,14 +23,6 @@

 # error "Never include <bits/stdio2.h> directly; use <stdio.h> instead."

 #endif

-extern int __sprintf_chk (char *__restrict __s, int __flag, size_t __slen,

-			  const char *__restrict __format, ...) __THROW

-    __attr_access ((__write_only__, 1, 3));

-extern int __vsprintf_chk (char *__restrict __s, int __flag, size_t __slen,

-			   const char *__restrict __format,

-			   __gnuc_va_list __ap) __THROW

-    __attr_access ((__write_only__, 1, 3));

-

 #ifdef __va_arg_pack

 __fortify_function int

 __NTH (sprintf (char *__restrict __s, const char *__restrict __fmt, ...))

@@ -54,15 +46,6 @@ __NTH (vsprintf (char *__restrict __s, const char *__restrict __fmt,

 }

 #if defined __USE_ISOC99 || defined __USE_UNIX98

-

-extern int __snprintf_chk (char *__restrict __s, size_t __n, int __flag,

-			   size_t __slen, const char *__restrict __format,

-			   ...) __THROW

-    __attr_access ((__write_only__, 1, 2));

-extern int __vsnprintf_chk (char *__restrict __s, size_t __n, int __flag,

-			    size_t __slen, const char *__restrict __format,

-			    __gnuc_va_list __ap) __THROW;

-

 # ifdef __va_arg_pack

 __fortify_function int

 __NTH (snprintf (char *__restrict __s, size_t __n,

@@ -89,15 +72,6 @@ __NTH (vsnprintf (char *__restrict __s, size_t __n,

 #endif

 #if __USE_FORTIFY_LEVEL > 1

-

-extern int __fprintf_chk (FILE *__restrict __stream, int __flag,

-			  const char *__restrict __format, ...);

-extern int __printf_chk (int __flag, const char *__restrict __format, ...);

-extern int __vfprintf_chk (FILE *__restrict __stream, int __flag,

-			   const char *__restrict __format, __gnuc_va_list __ap);

-extern int __vprintf_chk (int __flag, const char *__restrict __format,

-			  __gnuc_va_list __ap);

-

 # ifdef __va_arg_pack

 __fortify_function int

 fprintf (FILE *__restrict __stream, const char *__restrict __fmt, ...)

@@ -136,12 +110,6 @@ vfprintf (FILE *__restrict __stream,

 }

 # ifdef __USE_XOPEN2K8

-extern int __dprintf_chk (int __fd, int __flag, const char *__restrict __fmt,

-			  ...) __attribute__ ((__format__ (__printf__, 3, 4)));

-extern int __vdprintf_chk (int __fd, int __flag,

-			   const char *__restrict __fmt, __gnuc_va_list __arg)

-     __attribute__ ((__format__ (__printf__, 3, 0)));

-

 #  ifdef __va_arg_pack

 __fortify_function int

 dprintf (int __fd, const char *__restrict __fmt, ...)

@@ -162,23 +130,6 @@ vdprintf (int __fd, const char *__restrict __fmt, __gnuc_va_list __ap)

 # endif

 # ifdef __USE_GNU

-

-extern int __asprintf_chk (char **__restrict __ptr, int __flag,

-			   const char *__restrict __fmt, ...)

-     __THROW __attribute__ ((__format__ (__printf__, 3, 4))) __wur;

-extern int __vasprintf_chk (char **__restrict __ptr, int __flag,

-			    const char *__restrict __fmt, __gnuc_va_list __arg)

-     __THROW __attribute__ ((__format__ (__printf__, 3, 0))) __wur;

-extern int __obstack_printf_chk (struct obstack *__restrict __obstack,

-				 int __flag, const char *__restrict __format,

-				 ...)

-     __THROW __attribute__ ((__format__ (__printf__, 3, 4)));

-extern int __obstack_vprintf_chk (struct obstack *__restrict __obstack,

-				  int __flag,

-				  const char *__restrict __format,

-				  __gnuc_va_list __args)

-     __THROW __attribute__ ((__format__ (__printf__, 3, 0)));

-

 #  ifdef __va_arg_pack

 __fortify_function int

 __NTH (asprintf (char **__restrict __ptr, const char *__restrict __fmt, ...))

@@ -231,7 +182,6 @@ __NTH (obstack_vprintf (struct obstack *__restrict __obstack,

 #endif

 #if __GLIBC_USE (DEPRECATED_GETS)

-extern char *__gets_chk (char *__str, size_t) __wur;

 extern char *__REDIRECT (__gets_warn, (char *__str), gets)

      __wur __warnattr ("please use fgets or getline instead, gets can't "

 		       "specify buffer size");

@@ -245,9 +195,6 @@ gets (char *__str)

 }

 #endif

-extern char *__fgets_chk (char *__restrict __s, size_t __size, int __n,

-			  FILE *__restrict __stream)

-    __wur __attr_access ((__write_only__, 1, 3));

 extern char *__REDIRECT (__fgets_alias,

 			 (char *__restrict __s, int __n,

 			  FILE *__restrict __stream), fgets)

@@ -269,9 +216,6 @@ fgets (char *__restrict __s, int __n, FILE *__restrict __stream)

   return __fgets_chk (__s, sz, __n, __stream);

 }

-extern size_t __fread_chk (void *__restrict __ptr, size_t __ptrlen,

-			   size_t __size, size_t __n,

-			   FILE *__restrict __stream) __wur;

 extern size_t __REDIRECT (__fread_alias,

 			  (void *__restrict __ptr, size_t __size,

 			   size_t __n, FILE *__restrict __stream),

@@ -297,9 +241,6 @@ fread (void *__restrict __ptr, size_t __size, size_t __n,

 }

 #ifdef __USE_GNU

-extern char *__fgets_unlocked_chk (char *__restrict __s, size_t __size,

-				   int __n, FILE *__restrict __stream)

-    __wur __attr_access ((__write_only__, 1, 3));

 extern char *__REDIRECT (__fgets_unlocked_alias,

 			 (char *__restrict __s, int __n,

 			  FILE *__restrict __stream), fgets_unlocked)

@@ -324,9 +265,6 @@ fgets_unlocked (char *__restrict __s, int __n, FILE *__restrict __stream)

 #ifdef __USE_MISC

 # undef fread_unlocked

-extern size_t __fread_unlocked_chk (void *__restrict __ptr, size_t __ptrlen,

-				    size_t __size, size_t __n,

-				    FILE *__restrict __stream) __wur;

 extern size_t __REDIRECT (__fread_unlocked_alias,

 			  (void *__restrict __ptr, size_t __size,

 			   size_t __n, FILE *__restrict __stream),

diff --git a/libio/stdio.h b/libio/stdio.h

index abefe640e52d18d5..d36e61c56bbb3117 100644

--- a/libio/stdio.h

+++ b/libio/stdio.h

@@ -879,20 +879,27 @@ extern void funlockfile (FILE *__stream) __THROW;

 extern int __uflow (FILE *);

 extern int __overflow (FILE *, int);

+#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function

+/* Declare all functions from bits/stdio2-decl.h first.  */

+# include <bits/stdio2-decl.h>

+#endif

+

+/* The following headers provide asm redirections.  These redirections must

+   appear before the first usage of these functions, e.g. in bits/stdio.h.  */

+#if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1

+# include <bits/stdio-ldbl.h>

+#endif

+

 /* If we are compiling with optimizing read this file.  It contains

    several optimizing inline functions and macros.  */

 #ifdef __USE_EXTERN_INLINES

 # include <bits/stdio.h>

 #endif

 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function

+/* Now include the function definitions and redirects too.  */

 # include <bits/stdio2.h>

 #endif

-#include <bits/floatn.h>

-#if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1

-# include <bits/stdio-ldbl.h>

-#endif

-

 __END_DECLS

 #endif /* <stdio.h> included.  */