Update from Gnulib

This incorporates:
2020-05-09 stdio: don't redefine _GL_ATTRIBUTE_FORMAT
2020-05-09 dirent, stdlib, string: don't redefine _GL_ATTRIBUTE_PURE
2020-05-08 limits-h: define LONG_BIT correctly on Haiku/x86_64
2020-05-08 ignore-value tests: use module 'attribute'
2020-05-06 attribute: minor style fixes
* build-aux/config.sub, doc/misc/texinfo.tex, lib/attribute.h:
* lib/dirent.in.h, lib/limits.in.h, lib/stdio.in.h, lib/stdlib.in.h:
* lib/string.in.h, m4/gnulib-common.m4:
Copy from Gnulib.

1 files changed, 6 insertions, 4 deletions

diff --git a/lib/stdio.in.h b/lib/stdio.in.h
index 4a95f323a9a..6c338dd6c0b 100644
--- a/lib/stdio.in.h
+++ b/lib/stdio.in.h
@@ -62,10 +62,12 @@
    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 */
+#ifndef _GL_ATTRIBUTE_FORMAT
+# if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
+#  define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
+# else
+#  define _GL_ATTRIBUTE_FORMAT(spec) /* empty */
+# endif
 #endif
 
 /* _GL_ATTRIBUTE_FORMAT_PRINTF