2014-06-03  Ondřej Bílka  <neleai@seznam.cz>

	* argp/argp-fmtstream.h (_GL_ATTRIBUTE_FORMAT): Define.
	(argp_error, argp_failure): Use _GL_ATTRIBUTE_FORMAT.
	* argp/argp.h (__argp_fmtstream_printf): Likewise.

diff --git a/argp/argp-fmtstream.h b/argp/argp-fmtstream.h
index 1ed2834..fc07d91 100644
--- a/argp/argp-fmtstream.h
+++ b/argp/argp-fmtstream.h
@@ -29,17 +29,16 @@
 #include <string.h>
 #include <unistd.h>
 
-#ifndef __attribute__
-/* This feature is available in gcc versions 2.5 and later.  */
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__
-#  define __attribute__(Spec) /* empty */
-# endif
-/* The __-protected variants of `format' and `printf' attributes
-   are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7) || __STRICT_ANSI__
-#  define __format__ format
-#  define __printf__ printf
-# endif
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The __-protected variants of the attributes 'format' and 'printf' are
+   accepted by gcc versions 2.6.4 (effectively 2.7) and later.
+   We enable _GL_ATTRIBUTE_FORMAT only if these are supported too, because
+   gnulib and libintl do '#define printf __printf__' when they override
+   the 'printf' function.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
+# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
+#else
+# define _GL_ATTRIBUTE_FORMAT(spec) /* empty */
 #endif
 
 #if defined (__GNU_LIBRARY__) && defined (HAVE_LINEWRAP_H)
@@ -130,10 +127,10 @@ extern void argp_fmtstream_free (argp_fmtstream_t __fs);
 
 extern ssize_t __argp_fmtstream_printf (argp_fmtstream_t __fs,
 					const char *__fmt, ...)
-     __attribute__ ((__format__ (printf, 2, 3)));
+     _GL_ATTRIBUTE_FORMAT ((printf, 2, 3));
 extern ssize_t argp_fmtstream_printf (argp_fmtstream_t __fs,
 				      const char *__fmt, ...)
-     __attribute__ ((__format__ (printf, 2, 3)));
+     _GL_ATTRIBUTE_FORMAT ((printf, 2, 3));
 
 extern int __argp_fmtstream_putc (argp_fmtstream_t __fs, int __ch);
 extern int argp_fmtstream_putc (argp_fmtstream_t __fs, int __ch);
diff --git a/argp/argp.h b/argp/argp.h
index 0868228..6a1cc1b 100644
--- a/argp/argp.h
+++ b/argp/argp.h
@@ -35,17 +35,16 @@
 # define __NTH(fct) fct __THROW
 #endif
 
-#ifndef __attribute__
-/* This feature is available in gcc versions 2.5 and later.  */
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__
-#  define __attribute__(Spec) /* empty */
-# endif
-/* The __-protected variants of `format' and `printf' attributes
-   are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7) || __STRICT_ANSI__
-#  define __format__ format
-#  define __printf__ printf
-# endif
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The __-protected variants of the attributes 'format' and 'printf' are
+   accepted by gcc versions 2.6.4 (effectively 2.7) and later.
+   We enable _GL_ATTRIBUTE_FORMAT only if these are supported too, because
+   gnulib and libintl do '#define printf __printf__' when they override
+   the 'printf' function.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
+# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
+#else
+# define _GL_ATTRIBUTE_FORMAT(spec) /* empty */
 #endif
 
 /* GCC 2.95 and later have "__restrict"; C99 compilers have
@@ -503,10 +500,10 @@ extern void __argp_usage (const struct argp_state *__state);
    message, then exit (1).  */
 extern void argp_error (const struct argp_state *__restrict __state,
 			const char *__restrict __fmt, ...)
-     __attribute__ ((__format__ (__printf__, 2, 3)));
+     _GL_ATTRIBUTE_FORMAT ((__printf__, 2, 3));
 extern void __argp_error (const struct argp_state *__restrict __state,
 			  const char *__restrict __fmt, ...)
-     __attribute__ ((__format__ (__printf__, 2, 3)));
+    _GL_ATTRIBUTE_FORMAT ((__printf__, 2, 3));
 
 /* Similar to the standard gnu error-reporting function error(), but will
    respect the ARGP_NO_EXIT and ARGP_NO_ERRS flags in STATE, and will print
@@ -519,11 +516,11 @@ extern void __argp_error (const struct argp_state *__restrict __state,
 extern void argp_failure (const struct argp_state *__restrict __state,
 			  int __status, int __errnum,
 			  const char *__restrict __fmt, ...)
-     __attribute__ ((__format__ (__printf__, 4, 5)));
+     _GL_ATTRIBUTE_FORMAT ((__printf__, 4, 5));
 extern void __argp_failure (const struct argp_state *__restrict __state,
 			    int __status, int __errnum,
 			    const char *__restrict __fmt, ...)
-     __attribute__ ((__format__ (__printf__, 4, 5)));
+     _GL_ATTRIBUTE_FORMAT ((__printf__, 4, 5));
 
 /* Returns true if the option OPT is a valid short option.  */
 extern int _option_is_short (const struct argp_option *__opt) __THROW;