Sync with the latest Gnulib code (177f525)

Signed-off-by: Thomas Guyot-Sionnest <dermoth@aei.ca>

1 files changed, 521 insertions, 208 deletions

diff --git a/gl/string.in.h b/gl/string.in.h
index f021a3ed..eb8d7588 100644
--- a/gl/string.in.h
+++ b/gl/string.in.h
@@ -1,6 +1,6 @@
 /* A GNU-like <string.h>.
 
-   Copyright (C) 1995-1996, 2001-2008 Free Software Foundation, Inc.
+   Copyright (C) 1995-1996, 2001-2010 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -28,6 +28,13 @@
 #ifndef _GL_STRING_H
 #define _GL_STRING_H
 
+/* NetBSD 5.0 mis-defines NULL.  */
+#include <stddef.h>
+
+/* MirBSD defines mbslen as a macro.  */
+#if @GNULIB_MBSLEN@ && defined __MirBSD__
+# include <wchar.h>
+#endif
 
 #ifndef __attribute__
 /* This feature is available in gcc versions 2.5 and later.  */
@@ -41,60 +48,132 @@
 #endif
 
 
-/* The definition of GL_LINK_WARNING is copied here.  */
-
-
-#ifdef __cplusplus
-extern "C" {
+/* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
+
+/* The definition of _GL_ARG_NONNULL is copied here.  */
+
+/* The definition of _GL_WARN_ON_USE is copied here.  */
+
+
+/* Return the first instance of C within N bytes of S, or NULL.  */
+#if @GNULIB_MEMCHR@
+# if @REPLACE_MEMCHR@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define memchr rpl_memchr
+#  endif
+_GL_FUNCDECL_RPL (memchr, void *, (void const *__s, int __c, size_t __n)
+                                  __attribute__ ((__pure__))
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (memchr, void *, (void const *__s, int __c, size_t __n));
+# else
+#  if ! @HAVE_MEMCHR@
+_GL_FUNCDECL_SYS (memchr, void *, (void const *__s, int __c, size_t __n)
+                                  __attribute__ ((__pure__))
+                                  _GL_ARG_NONNULL ((1)));
+#  endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C" { const void * std::memchr (const void *, int, size_t); }
+       extern "C++" { void * std::memchr (void *, int, size_t); }  */
+_GL_CXXALIAS_SYS_CAST2 (memchr,
+                        void *, (void const *__s, int __c, size_t __n),
+                        void const *, (void const *__s, int __c, size_t __n));
+# endif
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (memchr, void *, (void *__s, int __c, size_t __n));
+_GL_CXXALIASWARN1 (memchr, void const *,
+                   (void const *__s, int __c, size_t __n));
+# else
+_GL_CXXALIASWARN (memchr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef memchr
+/* Assume memchr is always declared.  */
+_GL_WARN_ON_USE (memchr, "memchr has platform-specific bugs - "
+                 "use gnulib module memchr for portability" );
 #endif
 
-
 /* Return the first occurrence of NEEDLE in HAYSTACK.  */
 #if @GNULIB_MEMMEM@
 # if @REPLACE_MEMMEM@
-#  define memmem rpl_memmem
-# endif
-# if ! @HAVE_DECL_MEMMEM@ || @REPLACE_MEMMEM@
-extern void *memmem (void const *__haystack, size_t __haystack_len,
-		     void const *__needle, size_t __needle_len)
-  __attribute__ ((__pure__));
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define memmem rpl_memmem
+#  endif
+_GL_FUNCDECL_RPL (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len)
+                  __attribute__ ((__pure__)) _GL_ARG_NONNULL ((1, 3)));
+_GL_CXXALIAS_RPL (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len));
+# else
+#  if ! @HAVE_DECL_MEMMEM@
+_GL_FUNCDECL_SYS (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len)
+                  __attribute__ ((__pure__)) _GL_ARG_NONNULL ((1, 3)));
+#  endif
+_GL_CXXALIAS_SYS (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len));
 # endif
+_GL_CXXALIASWARN (memmem);
 #elif defined GNULIB_POSIXCHECK
 # undef memmem
-# define memmem(a,al,b,bl) \
-    (GL_LINK_WARNING ("memmem is unportable and often quadratic - " \
-                      "use gnulib module memmem-simple for portability, " \
-                      "and module memmem for speed" ), \
-     memmem (a, al, b, bl))
+# if HAVE_RAW_DECL_MEMMEM
+_GL_WARN_ON_USE (memmem, "memmem is unportable and often quadratic - "
+                 "use gnulib module memmem-simple for portability, "
+                 "and module memmem for speed" );
+# endif
 #endif
 
 /* Copy N bytes of SRC to DEST, return pointer to bytes after the
    last written byte.  */
 #if @GNULIB_MEMPCPY@
 # if ! @HAVE_MEMPCPY@
-extern void *mempcpy (void *restrict __dest, void const *restrict __src,
-		      size_t __n);
+_GL_FUNCDECL_SYS (mempcpy, void *,
+                  (void *restrict __dest, void const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
 # endif
+_GL_CXXALIAS_SYS (mempcpy, void *,
+                  (void *restrict __dest, void const *restrict __src,
+                   size_t __n));
+_GL_CXXALIASWARN (mempcpy);
 #elif defined GNULIB_POSIXCHECK
 # undef mempcpy
-# define mempcpy(a,b,n) \
-    (GL_LINK_WARNING ("mempcpy is unportable - " \
-                      "use gnulib module mempcpy for portability"), \
-     mempcpy (a, b, n))
+# if HAVE_RAW_DECL_MEMPCPY
+_GL_WARN_ON_USE (mempcpy, "mempcpy is unportable - "
+                 "use gnulib module mempcpy for portability");
+# endif
 #endif
 
 /* Search backwards through a block for a byte (specified as an int).  */
 #if @GNULIB_MEMRCHR@
 # if ! @HAVE_DECL_MEMRCHR@
-extern void *memrchr (void const *, int, size_t)
-  __attribute__ ((__pure__));
+_GL_FUNCDECL_SYS (memrchr, void *, (void const *, int, size_t)
+                                   __attribute__ ((__pure__))
+                                   _GL_ARG_NONNULL ((1)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const void * std::memrchr (const void *, int, size_t); }
+       extern "C++" { void * std::memrchr (void *, int, size_t); }  */
+_GL_CXXALIAS_SYS_CAST2 (memrchr,
+                        void *, (void const *, int, size_t),
+                        void const *, (void const *, int, size_t));
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (memrchr, void *, (void *, int, size_t));
+_GL_CXXALIASWARN1 (memrchr, void const *, (void const *, int, size_t));
+# else
+_GL_CXXALIASWARN (memrchr);
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef memrchr
-# define memrchr(a,b,c) \
-    (GL_LINK_WARNING ("memrchr is unportable - " \
-                      "use gnulib module memrchr for portability"), \
-     memrchr (a, b, c))
+# if HAVE_RAW_DECL_MEMRCHR
+_GL_WARN_ON_USE (memrchr, "memrchr is unportable - "
+                 "use gnulib module memrchr for portability");
+# endif
 #endif
 
 /* Find the first occurrence of C in S.  More efficient than
@@ -102,103 +181,191 @@ extern void *memrchr (void const *, int, size_t)
    occur within N bytes.  */
 #if @GNULIB_RAWMEMCHR@
 # if ! @HAVE_RAWMEMCHR@
-extern void *rawmemchr (void const *__s, int __c_in)
-  __attribute__ ((__pure__));
+_GL_FUNCDECL_SYS (rawmemchr, void *, (void const *__s, int __c_in)
+                                     __attribute__ ((__pure__))
+                                     _GL_ARG_NONNULL ((1)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const void * std::rawmemchr (const void *, int); }
+       extern "C++" { void * std::rawmemchr (void *, int); }  */
+_GL_CXXALIAS_SYS_CAST2 (rawmemchr,
+                        void *, (void const *__s, int __c_in),
+                        void const *, (void const *__s, int __c_in));
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (rawmemchr, void *, (void *__s, int __c_in));
+_GL_CXXALIASWARN1 (rawmemchr, void const *, (void const *__s, int __c_in));
+# else
+_GL_CXXALIASWARN (rawmemchr);
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef rawmemchr
-# define rawmemchr(a,b) \
-    (GL_LINK_WARNING ("rawmemchr is unportable - " \
-                      "use gnulib module rawmemchr for portability"), \
-     rawmemchr (a, b))
+# if HAVE_RAW_DECL_RAWMEMCHR
+_GL_WARN_ON_USE (rawmemchr, "rawmemchr is unportable - "
+                 "use gnulib module rawmemchr for portability");
+# endif
 #endif
 
 /* Copy SRC to DST, returning the address of the terminating '\0' in DST.  */
 #if @GNULIB_STPCPY@
 # if ! @HAVE_STPCPY@
-extern char *stpcpy (char *restrict __dst, char const *restrict __src);
+_GL_FUNCDECL_SYS (stpcpy, char *,
+                  (char *restrict __dst, char const *restrict __src)
+                  _GL_ARG_NONNULL ((1, 2)));
 # endif
+_GL_CXXALIAS_SYS (stpcpy, char *,
+                  (char *restrict __dst, char const *restrict __src));
+_GL_CXXALIASWARN (stpcpy);
 #elif defined GNULIB_POSIXCHECK
 # undef stpcpy
-# define stpcpy(a,b) \
-    (GL_LINK_WARNING ("stpcpy is unportable - " \
-                      "use gnulib module stpcpy for portability"), \
-     stpcpy (a, b))
+# if HAVE_RAW_DECL_STPCPY
+_GL_WARN_ON_USE (stpcpy, "stpcpy is unportable - "
+                 "use gnulib module stpcpy for portability");
+# endif
 #endif
 
 /* Copy no more than N bytes of SRC to DST, returning a pointer past the
    last non-NUL byte written into DST.  */
 #if @GNULIB_STPNCPY@
-# if ! @HAVE_STPNCPY@
-#  define stpncpy gnu_stpncpy
-extern char *stpncpy (char *restrict __dst, char const *restrict __src,
-		      size_t __n);
+# if @REPLACE_STPNCPY@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define stpncpy rpl_stpncpy
+#  endif
+_GL_FUNCDECL_RPL (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n));
+# else
+#  if ! @HAVE_STPNCPY@
+_GL_FUNCDECL_SYS (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
+#  endif
+_GL_CXXALIAS_SYS (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n));
 # endif
+_GL_CXXALIASWARN (stpncpy);
 #elif defined GNULIB_POSIXCHECK
 # undef stpncpy
-# define stpncpy(a,b,n) \
-    (GL_LINK_WARNING ("stpncpy is unportable - " \
-                      "use gnulib module stpncpy for portability"), \
-     stpncpy (a, b, n))
+# if HAVE_RAW_DECL_STPNCPY
+_GL_WARN_ON_USE (stpncpy, "stpncpy is unportable - "
+                 "use gnulib module stpncpy for portability");
+# endif
 #endif
 
 #if defined GNULIB_POSIXCHECK
 /* strchr() does not work with multibyte strings if the locale encoding is
    GB18030 and the character to be searched is a digit.  */
 # undef strchr
-# define strchr(s,c) \
-    (GL_LINK_WARNING ("strchr cannot work correctly on character strings " \
-                      "in some multibyte locales - " \
-                      "use mbschr if you care about internationalization"), \
-     strchr (s, c))
+/* Assume strchr is always declared.  */
+_GL_WARN_ON_USE (strchr, "strchr cannot work correctly on character strings "
+                 "in some multibyte locales - "
+                 "use mbschr if you care about internationalization");
 #endif
 
 /* Find the first occurrence of C in S or the final NUL byte.  */
 #if @GNULIB_STRCHRNUL@
 # if ! @HAVE_STRCHRNUL@
-extern char *strchrnul (char const *__s, int __c_in)
-  __attribute__ ((__pure__));
+_GL_FUNCDECL_SYS (strchrnul, char *, (char const *__s, int __c_in)
+                                     __attribute__ ((__pure__))
+                                     _GL_ARG_NONNULL ((1)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * std::strchrnul (const char *, int); }
+       extern "C++" { char * std::strchrnul (char *, int); }  */
+_GL_CXXALIAS_SYS_CAST2 (strchrnul,
+                        char *, (char const *__s, int __c_in),
+                        char const *, (char const *__s, int __c_in));
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strchrnul, char *, (char *__s, int __c_in));
+_GL_CXXALIASWARN1 (strchrnul, char const *, (char const *__s, int __c_in));
+# else
+_GL_CXXALIASWARN (strchrnul);
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef strchrnul
-# define strchrnul(a,b) \
-    (GL_LINK_WARNING ("strchrnul is unportable - " \
-                      "use gnulib module strchrnul for portability"), \
-     strchrnul (a, b))
+# if HAVE_RAW_DECL_STRCHRNUL
+_GL_WARN_ON_USE (strchrnul, "strchrnul is unportable - "
+                 "use gnulib module strchrnul for portability");
+# endif
 #endif
 
 /* Duplicate S, returning an identical malloc'd string.  */
 #if @GNULIB_STRDUP@
 # if @REPLACE_STRDUP@
-#  undef strdup
-#  define strdup rpl_strdup
-# endif
-# if !(@HAVE_DECL_STRDUP@ || defined strdup) || @REPLACE_STRDUP@
-extern char *strdup (char const *__s);
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strdup
+#   define strdup rpl_strdup
+#  endif
+_GL_FUNCDECL_RPL (strdup, char *, (char const *__s) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strdup, char *, (char const *__s));
+# else
+#  if !(@HAVE_DECL_STRDUP@ || defined strdup)
+_GL_FUNCDECL_SYS (strdup, char *, (char const *__s) _GL_ARG_NONNULL ((1)));
+#  endif
+_GL_CXXALIAS_SYS (strdup, char *, (char const *__s));
 # endif
+_GL_CXXALIASWARN (strdup);
 #elif defined GNULIB_POSIXCHECK
 # undef strdup
-# define strdup(a) \
-    (GL_LINK_WARNING ("strdup is unportable - " \
-                      "use gnulib module strdup for portability"), \
-     strdup (a))
+# if HAVE_RAW_DECL_STRDUP
+_GL_WARN_ON_USE (strdup, "strdup is unportable - "
+                 "use gnulib module strdup for portability");
+# endif
+#endif
+
+/* Append no more than N characters from SRC onto DEST.  */
+#if @GNULIB_STRNCAT@
+# if @REPLACE_STRNCAT@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strncat
+#   define strncat rpl_strncat
+#  endif
+_GL_FUNCDECL_RPL (strncat, char *, (char *dest, const char *src, size_t n)
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strncat, char *, (char *dest, const char *src, size_t n));
+# else
+_GL_CXXALIAS_SYS (strncat, char *, (char *dest, const char *src, size_t n));
+# endif
+_GL_CXXALIASWARN (strncat);
+#elif defined GNULIB_POSIXCHECK
+# undef strncat
+# if HAVE_RAW_DECL_STRNCAT
+_GL_WARN_ON_USE (strncat, "strncat is unportable - "
+                 "use gnulib module strncat for portability");
+# endif
 #endif
 
 /* Return a newly allocated copy of at most N bytes of STRING.  */
 #if @GNULIB_STRNDUP@
-# if ! @HAVE_STRNDUP@
-#  undef strndup
-#  define strndup rpl_strndup
-# endif
-# if ! @HAVE_STRNDUP@ || ! @HAVE_DECL_STRNDUP@
-extern char *strndup (char const *__string, size_t __n);
+# if @REPLACE_STRNDUP@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strndup
+#   define strndup rpl_strndup
+#  endif
+_GL_FUNCDECL_RPL (strndup, char *, (char const *__string, size_t __n)
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strndup, char *, (char const *__string, size_t __n));
+# else
+#  if ! @HAVE_DECL_STRNDUP@
+_GL_FUNCDECL_SYS (strndup, char *, (char const *__string, size_t __n)
+                                   _GL_ARG_NONNULL ((1)));
+#  endif
+_GL_CXXALIAS_SYS (strndup, char *, (char const *__string, size_t __n));
 # endif
+_GL_CXXALIASWARN (strndup);
 #elif defined GNULIB_POSIXCHECK
 # undef strndup
-# define strndup(a,n) \
-    (GL_LINK_WARNING ("strndup is unportable - " \
-                      "use gnulib module strndup for portability"), \
-     strndup (a, n))
+# if HAVE_RAW_DECL_STRNDUP
+_GL_WARN_ON_USE (strndup, "strndup is unportable - "
+                 "use gnulib module strndup for portability");
+# endif
 #endif
 
 /* Find the length (number of bytes) of STRING, but scan at most
@@ -206,15 +373,18 @@ extern char *strndup (char const *__string, size_t __n);
    return MAXLEN.  */
 #if @GNULIB_STRNLEN@
 # if ! @HAVE_DECL_STRNLEN@
-extern size_t strnlen (char const *__string, size_t __maxlen)
-  __attribute__ ((__pure__));
+_GL_FUNCDECL_SYS (strnlen, size_t, (char const *__string, size_t __maxlen)
+                                   __attribute__ ((__pure__))
+                                   _GL_ARG_NONNULL ((1)));
 # endif
+_GL_CXXALIAS_SYS (strnlen, size_t, (char const *__string, size_t __maxlen));
+_GL_CXXALIASWARN (strnlen);
 #elif defined GNULIB_POSIXCHECK
 # undef strnlen
-# define strnlen(a,n) \
-    (GL_LINK_WARNING ("strnlen is unportable - " \
-                      "use gnulib module strnlen for portability"), \
-     strnlen (a, n))
+# if HAVE_RAW_DECL_STRNLEN
+_GL_WARN_ON_USE (strnlen, "strnlen is unportable - "
+                 "use gnulib module strnlen for portability");
+# endif
 #endif
 
 #if defined GNULIB_POSIXCHECK
@@ -223,18 +393,32 @@ extern size_t strnlen (char const *__string, size_t __maxlen)
    locale encoding is GB18030 and one of the characters to be searched is a
    digit.  */
 # undef strcspn
-# define strcspn(s,a) \
-    (GL_LINK_WARNING ("strcspn cannot work correctly on character strings " \
-                      "in multibyte locales - " \
-                      "use mbscspn if you care about internationalization"), \
-     strcspn (s, a))
+/* Assume strcspn is always declared.  */
+_GL_WARN_ON_USE (strcspn, "strcspn cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbscspn if you care about internationalization");
 #endif
 
 /* Find the first occurrence in S of any character in ACCEPT.  */
 #if @GNULIB_STRPBRK@
 # if ! @HAVE_STRPBRK@
-extern char *strpbrk (char const *__s, char const *__accept)
-  __attribute__ ((__pure__));
+_GL_FUNCDECL_SYS (strpbrk, char *, (char const *__s, char const *__accept)
+                                   __attribute__ ((__pure__))
+                                   _GL_ARG_NONNULL ((1, 2)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C" { const char * strpbrk (const char *, const char *); }
+       extern "C++" { char * strpbrk (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strpbrk,
+                        char *, (char const *__s, char const *__accept),
+                        const char *, (char const *__s, char const *__accept));
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strpbrk, char *, (char *__s, char const *__accept));
+_GL_CXXALIASWARN1 (strpbrk, char const *,
+                   (char const *__s, char const *__accept));
+# else
+_GL_CXXALIASWARN (strpbrk);
 # endif
 # if defined GNULIB_POSIXCHECK
 /* strpbrk() assumes the second argument is a list of single-byte characters.
@@ -242,40 +426,36 @@ extern char *strpbrk (char const *__s, char const *__accept)
    locale encoding is GB18030 and one of the characters to be searched is a
    digit.  */
 #  undef strpbrk
-#  define strpbrk(s,a) \
-     (GL_LINK_WARNING ("strpbrk cannot work correctly on character strings " \
-                       "in multibyte locales - " \
-                       "use mbspbrk if you care about internationalization"), \
-      strpbrk (s, a))
+_GL_WARN_ON_USE (strpbrk, "strpbrk cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbspbrk if you care about internationalization");
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef strpbrk
-# define strpbrk(s,a) \
-    (GL_LINK_WARNING ("strpbrk is unportable - " \
-                      "use gnulib module strpbrk for portability"), \
-     strpbrk (s, a))
+# if HAVE_RAW_DECL_STRPBRK
+_GL_WARN_ON_USE (strpbrk, "strpbrk is unportable - "
+                 "use gnulib module strpbrk for portability");
+# endif
 #endif
 
 #if defined GNULIB_POSIXCHECK
 /* strspn() assumes the second argument is a list of single-byte characters.
    Even in this simple case, it cannot work with multibyte strings.  */
 # undef strspn
-# define strspn(s,a) \
-    (GL_LINK_WARNING ("strspn cannot work correctly on character strings " \
-                      "in multibyte locales - " \
-                      "use mbsspn if you care about internationalization"), \
-     strspn (s, a))
+/* Assume strspn is always declared.  */
+_GL_WARN_ON_USE (strspn, "strspn cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbsspn if you care about internationalization");
 #endif
 
 #if defined GNULIB_POSIXCHECK
 /* strrchr() does not work with multibyte strings if the locale encoding is
    GB18030 and the character to be searched is a digit.  */
 # undef strrchr
-# define strrchr(s,c) \
-    (GL_LINK_WARNING ("strrchr cannot work correctly on character strings " \
-                      "in some multibyte locales - " \
-                      "use mbsrchr if you care about internationalization"), \
-     strrchr (s, c))
+/* Assume strrchr is always declared.  */
+_GL_WARN_ON_USE (strrchr, "strrchr cannot work correctly on character strings "
+                 "in some multibyte locales - "
+                 "use mbsrchr if you care about internationalization");
 #endif
 
 /* Search the next delimiter (char listed in DELIM) starting at *STRINGP.
@@ -296,29 +476,51 @@ extern char *strpbrk (char const *__s, char const *__accept)
    See also strtok_r().  */
 #if @GNULIB_STRSEP@
 # if ! @HAVE_STRSEP@
-extern char *strsep (char **restrict __stringp, char const *restrict __delim);
+_GL_FUNCDECL_SYS (strsep, char *,
+                  (char **restrict __stringp, char const *restrict __delim)
+                  _GL_ARG_NONNULL ((1, 2)));
 # endif
+_GL_CXXALIAS_SYS (strsep, char *,
+                  (char **restrict __stringp, char const *restrict __delim));
+_GL_CXXALIASWARN (strsep);
 # if defined GNULIB_POSIXCHECK
 #  undef strsep
-#  define strsep(s,d) \
-     (GL_LINK_WARNING ("strsep cannot work correctly on character strings " \
-                       "in multibyte locales - " \
-                       "use mbssep if you care about internationalization"), \
-      strsep (s, d))
+_GL_WARN_ON_USE (strsep, "strsep cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbssep if you care about internationalization");
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef strsep
-# define strsep(s,d) \
-    (GL_LINK_WARNING ("strsep is unportable - " \
-                      "use gnulib module strsep for portability"), \
-     strsep (s, d))
+# if HAVE_RAW_DECL_STRSEP
+_GL_WARN_ON_USE (strsep, "strsep is unportable - "
+                 "use gnulib module strsep for portability");
+# endif
 #endif
 
 #if @GNULIB_STRSTR@
 # if @REPLACE_STRSTR@
-#  define strstr rpl_strstr
-char *strstr (const char *haystack, const char *needle)
-  __attribute__ ((__pure__));
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strstr rpl_strstr
+#  endif
+_GL_FUNCDECL_RPL (strstr, char *, (const char *haystack, const char *needle)
+                                  __attribute__ ((__pure__))
+                                  _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strstr, char *, (const char *haystack, const char *needle));
+# else
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * strstr (const char *, const char *); }
+       extern "C++" { char * strstr (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strstr,
+                        char *, (const char *haystack, const char *needle),
+                        const char *, (const char *haystack, const char *needle));
+# endif
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strstr, char *, (char *haystack, const char *needle));
+_GL_CXXALIASWARN1 (strstr, const char *,
+                   (const char *haystack, const char *needle));
+# else
+_GL_CXXALIASWARN (strstr);
 # endif
 #elif defined GNULIB_POSIXCHECK
 /* strstr() does not work with multibyte strings if the locale encoding is
@@ -326,48 +528,70 @@ char *strstr (const char *haystack, const char *needle)
    POSIX says that it operates on "strings", and "string" in POSIX is defined
    as a sequence of bytes, not of characters.  */
 # undef strstr
-# define strstr(a,b) \
-    (GL_LINK_WARNING ("strstr is quadratic on many systems, and cannot " \
-                      "work correctly on character strings in most "    \
-                      "multibyte locales - " \
-                      "use mbsstr if you care about internationalization, " \
-                      "or use strstr if you care about speed"), \
-     strstr (a, b))
+/* Assume strstr is always declared.  */
+_GL_WARN_ON_USE (strstr, "strstr is quadratic on many systems, and cannot "
+                 "work correctly on character strings in most "
+                 "multibyte locales - "
+                 "use mbsstr if you care about internationalization, "
+                 "or use strstr if you care about speed");
 #endif
 
 /* Find the first occurrence of NEEDLE in HAYSTACK, using case-insensitive
    comparison.  */
 #if @GNULIB_STRCASESTR@
 # if @REPLACE_STRCASESTR@
-#  define strcasestr rpl_strcasestr
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strcasestr rpl_strcasestr
+#  endif
+_GL_FUNCDECL_RPL (strcasestr, char *,
+                  (const char *haystack, const char *needle)
+                  __attribute__ ((__pure__)) _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strcasestr, char *,
+                  (const char *haystack, const char *needle));
+# else
+#  if ! @HAVE_STRCASESTR@
+_GL_FUNCDECL_SYS (strcasestr, char *,
+                  (const char *haystack, const char *needle)
+                  __attribute__ ((__pure__)) _GL_ARG_NONNULL ((1, 2)));
+#  endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * strcasestr (const char *, const char *); }
+       extern "C++" { char * strcasestr (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strcasestr,
+                        char *, (const char *haystack, const char *needle),
+                        const char *, (const char *haystack, const char *needle));
 # endif
-# if ! @HAVE_STRCASESTR@ || @REPLACE_STRCASESTR@
-extern char *strcasestr (const char *haystack, const char *needle)
-  __attribute__ ((__pure__));
+# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 10 \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strcasestr, char *, (char *haystack, const char *needle));
+_GL_CXXALIASWARN1 (strcasestr, const char *,
+                   (const char *haystack, const char *needle));
+# else
+_GL_CXXALIASWARN (strcasestr);
 # endif
 #elif defined GNULIB_POSIXCHECK
 /* strcasestr() does not work with multibyte strings:
    It is a glibc extension, and glibc implements it only for unibyte
    locales.  */
 # undef strcasestr
-# define strcasestr(a,b) \
-    (GL_LINK_WARNING ("strcasestr does work correctly on character strings " \
-                      "in multibyte locales - " \
-                      "use mbscasestr if you care about " \
-                      "internationalization, or use c-strcasestr if you want " \
-                      "a locale independent function"), \
-     strcasestr (a, b))
+# if HAVE_RAW_DECL_STRCASESTR
+_GL_WARN_ON_USE (strcasestr, "strcasestr does work correctly on character "
+                 "strings in multibyte locales - "
+                 "use mbscasestr if you care about "
+                 "internationalization, or use c-strcasestr if you want "
+                 "a locale independent function");
+# endif
 #endif
 
 /* Parse S into tokens separated by characters in DELIM.
    If S is NULL, the saved pointer in SAVE_PTR is used as
    the next starting point.  For example:
-	char s[] = "-abc-=-def";
-	char *sp;
-	x = strtok_r(s, "-", &sp);	// x = "abc", sp = "=-def"
-	x = strtok_r(NULL, "-=", &sp);	// x = "def", sp = NULL
-	x = strtok_r(NULL, "=", &sp);	// x = NULL
-		// s = "abc\0-def\0"
+        char s[] = "-abc-=-def";
+        char *sp;
+        x = strtok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
+        x = strtok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
+        x = strtok_r(NULL, "=", &sp);   // x = NULL
+                // s = "abc\0-def\0"
 
    This is a variant of strtok() that is multithread-safe.
 
@@ -382,24 +606,44 @@ extern char *strcasestr (const char *haystack, const char *needle)
 
    See also strsep().  */
 #if @GNULIB_STRTOK_R@
-# if ! @HAVE_DECL_STRTOK_R@
-extern char *strtok_r (char *restrict s, char const *restrict delim,
-		       char **restrict save_ptr);
+# if @REPLACE_STRTOK_R@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strtok_r
+#   define strtok_r rpl_strtok_r
+#  endif
+_GL_FUNCDECL_RPL (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr)
+                  _GL_ARG_NONNULL ((2, 3)));
+_GL_CXXALIAS_RPL (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr));
+# else
+#  if @UNDEFINE_STRTOK_R@ || defined GNULIB_POSIXCHECK
+#   undef strtok_r
+#  endif
+#  if ! @HAVE_DECL_STRTOK_R@
+_GL_FUNCDECL_SYS (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr)
+                  _GL_ARG_NONNULL ((2, 3)));
+#  endif
+_GL_CXXALIAS_SYS (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr));
 # endif
+_GL_CXXALIASWARN (strtok_r);
 # if defined GNULIB_POSIXCHECK
-#  undef strtok_r
-#  define strtok_r(s,d,p) \
-     (GL_LINK_WARNING ("strtok_r cannot work correctly on character strings " \
-                       "in multibyte locales - " \
-                       "use mbstok_r if you care about internationalization"), \
-      strtok_r (s, d, p))
+_GL_WARN_ON_USE (strtok_r, "strtok_r cannot work correctly on character "
+                 "strings in multibyte locales - "
+                 "use mbstok_r if you care about internationalization");
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef strtok_r
-# define strtok_r(s,d,p) \
-    (GL_LINK_WARNING ("strtok_r is unportable - " \
-                      "use gnulib module strtok_r for portability"), \
-     strtok_r (s, d, p))
+# if HAVE_RAW_DECL_STRTOK_R
+_GL_WARN_ON_USE (strtok_r, "strtok_r is unportable - "
+                 "use gnulib module strtok_r for portability");
+# endif
 #endif
 
 
@@ -409,13 +653,27 @@ extern char *strtok_r (char *restrict s, char const *restrict delim,
 #if @GNULIB_MBSLEN@
 /* Return the number of multibyte characters in the character string STRING.
    This considers multibyte characters, unlike strlen, which counts bytes.  */
-extern size_t mbslen (const char *string);
+# ifdef __MirBSD__  /* MirBSD defines mbslen as a macro.  Override it.  */
+#  undef mbslen
+# endif
+# if @HAVE_MBSLEN@  /* AIX, OSF/1, MirBSD define mbslen already in libc.  */
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbslen rpl_mbslen
+#  endif
+_GL_FUNCDECL_RPL (mbslen, size_t, (const char *string) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbslen, size_t, (const char *string));
+# else
+_GL_FUNCDECL_SYS (mbslen, size_t, (const char *string) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbslen, size_t, (const char *string));
+# endif
+_GL_CXXALIASWARN (mbslen);
 #endif
 
 #if @GNULIB_MBSNLEN@
 /* Return the number of multibyte characters in the character string starting
    at STRING and ending at STRING + LEN.  */
-extern size_t mbsnlen (const char *string, size_t len);
+_GL_EXTERN_C size_t mbsnlen (const char *string, size_t len)
+     _GL_ARG_NONNULL ((1));
 #endif
 
 #if @GNULIB_MBSCHR@
@@ -423,8 +681,19 @@ extern size_t mbsnlen (const char *string, size_t len);
    and return a pointer to it.  Return NULL if C is not found in STRING.
    Unlike strchr(), this function works correctly in multibyte locales with
    encodings such as GB18030.  */
-# define mbschr rpl_mbschr /* avoid collision with HP-UX function */
-extern char * mbschr (const char *string, int c);
+# if defined __hpux
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbschr rpl_mbschr /* avoid collision with HP-UX function */
+#  endif
+_GL_FUNCDECL_RPL (mbschr, char *, (const char *string, int c)
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbschr, char *, (const char *string, int c));
+# else
+_GL_FUNCDECL_SYS (mbschr, char *, (const char *string, int c)
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbschr, char *, (const char *string, int c));
+# endif
+_GL_CXXALIASWARN (mbschr);
 #endif
 
 #if @GNULIB_MBSRCHR@
@@ -432,8 +701,19 @@ extern char * mbschr (const char *string, int c);
    and return a pointer to it.  Return NULL if C is not found in STRING.
    Unlike strrchr(), this function works correctly in multibyte locales with
    encodings such as GB18030.  */
-# define mbsrchr rpl_mbsrchr /* avoid collision with HP-UX function */
-extern char * mbsrchr (const char *string, int c);
+# if defined __hpux
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbsrchr rpl_mbsrchr /* avoid collision with HP-UX function */
+#  endif
+_GL_FUNCDECL_RPL (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbsrchr, char *, (const char *string, int c));
+# else
+_GL_FUNCDECL_SYS (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbsrchr, char *, (const char *string, int c));
+# endif
+_GL_CXXALIASWARN (mbsrchr);
 #endif
 
 #if @GNULIB_MBSSTR@
@@ -441,7 +721,8 @@ extern char * mbsrchr (const char *string, int c);
    string HAYSTACK.  Return NULL if NEEDLE is not found in HAYSTACK.
    Unlike strstr(), this function works correctly in multibyte locales with
    encodings different from UTF-8.  */
-extern char * mbsstr (const char *haystack, const char *needle);
+_GL_EXTERN_C char * mbsstr (const char *haystack, const char *needle)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSCASECMP@
@@ -451,7 +732,8 @@ extern char * mbsstr (const char *haystack, const char *needle);
    Note: This function may, in multibyte locales, return 0 for strings of
    different lengths!
    Unlike strcasecmp(), this function works correctly in multibyte locales.  */
-extern int mbscasecmp (const char *s1, const char *s2);
+_GL_EXTERN_C int mbscasecmp (const char *s1, const char *s2)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSNCASECMP@
@@ -464,7 +746,8 @@ extern int mbscasecmp (const char *s1, const char *s2);
    of different lengths!
    Unlike strncasecmp(), this function works correctly in multibyte locales.
    But beware that N is not a byte count but a character count!  */
-extern int mbsncasecmp (const char *s1, const char *s2, size_t n);
+_GL_EXTERN_C int mbsncasecmp (const char *s1, const char *s2, size_t n)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSPCASECMP@
@@ -477,7 +760,8 @@ extern int mbsncasecmp (const char *s1, const char *s2, size_t n);
    smaller length than PREFIX!
    Unlike strncasecmp(), this function works correctly in multibyte
    locales.  */
-extern char * mbspcasecmp (const char *string, const char *prefix);
+_GL_EXTERN_C char * mbspcasecmp (const char *string, const char *prefix)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSCASESTR@
@@ -486,7 +770,8 @@ extern char * mbspcasecmp (const char *string, const char *prefix);
    Note: This function may, in multibyte locales, return success even if
    strlen (haystack) < strlen (needle) !
    Unlike strcasestr(), this function works correctly in multibyte locales.  */
-extern char * mbscasestr (const char *haystack, const char *needle);
+_GL_EXTERN_C char * mbscasestr (const char *haystack, const char *needle)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSCSPN@
@@ -495,7 +780,8 @@ extern char * mbscasestr (const char *haystack, const char *needle);
    beginning of the string to this occurrence, or to the end of the string
    if none exists.
    Unlike strcspn(), this function works correctly in multibyte locales.  */
-extern size_t mbscspn (const char *string, const char *accept);
+_GL_EXTERN_C size_t mbscspn (const char *string, const char *accept)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSPBRK@
@@ -503,8 +789,19 @@ extern size_t mbscspn (const char *string, const char *accept);
    in the character string ACCEPT.  Return the pointer to it, or NULL if none
    exists.
    Unlike strpbrk(), this function works correctly in multibyte locales.  */
-# define mbspbrk rpl_mbspbrk /* avoid collision with HP-UX function */
-extern char * mbspbrk (const char *string, const char *accept);
+# if defined __hpux
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbspbrk rpl_mbspbrk /* avoid collision with HP-UX function */
+#  endif
+_GL_FUNCDECL_RPL (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (mbspbrk, char *, (const char *string, const char *accept));
+# else
+_GL_FUNCDECL_SYS (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_SYS (mbspbrk, char *, (const char *string, const char *accept));
+# endif
+_GL_CXXALIASWARN (mbspbrk);
 #endif
 
 #if @GNULIB_MBSSPN@
@@ -513,7 +810,8 @@ extern char * mbspbrk (const char *string, const char *accept);
    beginning of the string to this occurrence, or to the end of the string
    if none exists.
    Unlike strspn(), this function works correctly in multibyte locales.  */
-extern size_t mbsspn (const char *string, const char *reject);
+_GL_EXTERN_C size_t mbsspn (const char *string, const char *reject)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSSEP@
@@ -531,7 +829,8 @@ extern size_t mbsspn (const char *string, const char *reject);
    Caveat: The identity of the delimiting character is lost.
 
    See also mbstok_r().  */
-extern char * mbssep (char **stringp, const char *delim);
+_GL_EXTERN_C char * mbssep (char **stringp, const char *delim)
+     _GL_ARG_NONNULL ((1, 2));
 #endif
 
 #if @GNULIB_MBSTOK_R@
@@ -539,67 +838,81 @@ extern char * mbssep (char **stringp, const char *delim);
    the character string DELIM.
    If STRING is NULL, the saved pointer in SAVE_PTR is used as
    the next starting point.  For example:
-	char s[] = "-abc-=-def";
-	char *sp;
-	x = mbstok_r(s, "-", &sp);	// x = "abc", sp = "=-def"
-	x = mbstok_r(NULL, "-=", &sp);	// x = "def", sp = NULL
-	x = mbstok_r(NULL, "=", &sp);	// x = NULL
-		// s = "abc\0-def\0"
+        char s[] = "-abc-=-def";
+        char *sp;
+        x = mbstok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
+        x = mbstok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
+        x = mbstok_r(NULL, "=", &sp);   // x = NULL
+                // s = "abc\0-def\0"
 
    Caveat: It modifies the original string.
    Caveat: These functions cannot be used on constant strings.
    Caveat: The identity of the delimiting character is lost.
 
    See also mbssep().  */
-extern char * mbstok_r (char *string, const char *delim, char **save_ptr);
+_GL_EXTERN_C char * mbstok_r (char *string, const char *delim, char **save_ptr)
+     _GL_ARG_NONNULL ((2, 3));
 #endif
 
 /* Map any int, typically from errno, into an error message.  */
 #if @GNULIB_STRERROR@
 # if @REPLACE_STRERROR@
-#  undef strerror
-#  define strerror rpl_strerror
-extern char *strerror (int);
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strerror
+#   define strerror rpl_strerror
+#  endif
+_GL_FUNCDECL_RPL (strerror, char *, (int));
+_GL_CXXALIAS_RPL (strerror, char *, (int));
+# else
+_GL_CXXALIAS_SYS (strerror, char *, (int));
 # endif
+_GL_CXXALIASWARN (strerror);
 #elif defined GNULIB_POSIXCHECK
 # undef strerror
-# define strerror(e) \
-    (GL_LINK_WARNING ("strerror is unportable - " \
-                      "use gnulib module strerror to guarantee non-NULL result"), \
-     strerror (e))
+/* Assume strerror is always declared.  */
+_GL_WARN_ON_USE (strerror, "strerror is unportable - "
+                 "use gnulib module strerror to guarantee non-NULL result");
 #endif
 
 #if @GNULIB_STRSIGNAL@
 # if @REPLACE_STRSIGNAL@
-#  define strsignal rpl_strsignal
-# endif
-# if ! @HAVE_DECL_STRSIGNAL@ || @REPLACE_STRSIGNAL@
-extern char *strsignal (int __sig);
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strsignal rpl_strsignal
+#  endif
+_GL_FUNCDECL_RPL (strsignal, char *, (int __sig));
+_GL_CXXALIAS_RPL (strsignal, char *, (int __sig));
+# else
+#  if ! @HAVE_DECL_STRSIGNAL@
+_GL_FUNCDECL_SYS (strsignal, char *, (int __sig));
+#  endif
+/* Need to cast, because on Cygwin 1.5.x systems, the return type is
+   'const char *'.  */
+_GL_CXXALIAS_SYS_CAST (strsignal, char *, (int __sig));
 # endif
+_GL_CXXALIASWARN (strsignal);
 #elif defined GNULIB_POSIXCHECK
 # undef strsignal
-# define strsignal(a) \
-    (GL_LINK_WARNING ("strsignal is unportable - " \
-                      "use gnulib module strsignal for portability"), \
-     strsignal (a))
+# if HAVE_RAW_DECL_STRSIGNAL
+_GL_WARN_ON_USE (strsignal, "strsignal is unportable - "
+                 "use gnulib module strsignal for portability");
+# endif
 #endif
 
 #if @GNULIB_STRVERSCMP@
 # if !@HAVE_STRVERSCMP@
-extern int strverscmp (const char *, const char *);
+_GL_FUNCDECL_SYS (strverscmp, int, (const char *, const char *)
+                                   _GL_ARG_NONNULL ((1, 2)));
 # endif
+_GL_CXXALIAS_SYS (strverscmp, int, (const char *, const char *));
+_GL_CXXALIASWARN (strverscmp);
 #elif defined GNULIB_POSIXCHECK
 # undef strverscmp
-# define strverscmp(a, b) \
-    (GL_LINK_WARNING ("strverscmp is unportable - " \
-                      "use gnulib module strverscmp for portability"), \
-     strverscmp (a, b))
+# if HAVE_RAW_DECL_STRVERSCMP
+_GL_WARN_ON_USE (strverscmp, "strverscmp is unportable - "
+                 "use gnulib module strverscmp for portability");
+# endif
 #endif
 
 
-#ifdef __cplusplus
-}
-#endif
-
 #endif /* _GL_STRING_H */
 #endif /* _GL_STRING_H */