Probably an unpopular change, but...

In order to get consistent behaviour on linux with various gcc versions,
I am defining _GNU_SOURCE in ompi_config.h and changing the definition
of asprintf, etc.

Problems:
1) autoconf was defining _GNU_SOURCE for its tests, but we were not
setting it
2) g++ sets it by default (I think)
3) some version of gcc set it by default

If somebody knows a consistent solution for these problems then we can
revert to not setting it.

This commit was SVN r2230.

configure.ac

@@ -42,6 +42,12 @@ ompi_show_subtitle "Initialization, setup"
 
 AM_INIT_AUTOMAKE(openmpi, $OMPI_VERSION, 'no')
 
+#
+# GNU C and autotools are inconsistent about whether this is defined
+# so let's make it true everywhere for now...
+#
+AC_GNU_SOURCE
+
 OMPI_TOP_BUILDDIR="`pwd`"
 AC_SUBST(OMPI_TOP_BUILDDIR)
 cd "$srcdir"

include/ompi_config_bottom.h

@@ -108,19 +108,47 @@ typedef struct {
 /*
  * printf functions for portability
  */
+
+#if !defined(HAVE_VASPRINTF) || !defined(HAVE_VSNPRINTF)
+#if __STDC__
+#include <stdarg.h>
+#else
+#ifdef __cplusplus
+#include <stdarg.h>
+#else
+#include <varargs.h>
+#endif
+#endif /* __STDC__ */
+#endif
+
+#if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
+#include <stdlib.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #ifndef HAVE_ASPRINTF
-# include "util/printf.h"
+int ompi_asprintf(char **, const char *, ...);
 # define asprintf ompi_asprintf
 #endif
+
 #ifndef HAVE_SNPRINTF
-# include "util/printf.h"
+int ompi_snprintf(char *, size_t, const char *, ...);
 # define snprintf ompi_snprintf
 #endif
+
 #ifndef HAVE_VASPRINTF
-# include "util/printf.h"
+int ompi_vasprintf(char **, const char *, va_list);
 # define vasprintf ompi_vasprintf
 #endif
+
 #ifndef HAVE_VSNPRINTF
-# include "util/printf.h"
+int ompi_vsnprintf(char *, size_t, const char *, va_list);
 # define vsnprintf ompi_vsnprintf
 #endif
+
+#ifdef __cplusplus
+}
+#endif