Ensure that other packages defining PACKAGE_ macros don't hurt us, and protect others from our PACKAGE_ macros.

This commit was SVN r24571.

configure.ac

@@ -10,7 +10,7 @@
 #                         University of Stuttgart.  All rights reserved.
 # Copyright (c) 2004-2005 The Regents of the University of California.
 #                         All rights reserved.
-# Copyright (c) 2006-2010 Cisco Systems, Inc.  All rights reserved.
+# Copyright (c) 2006-2011 Cisco Systems, Inc.  All rights reserved.
 # Copyright (c) 2006-2008 Sun Microsystems, Inc.  All rights reserved.
 # Copyright (c) 2006-2007 Los Alamos National Security, LLC.  All rights
 #                         reserved. 
@@ -208,6 +208,9 @@ AH_TOP([/* -*- c -*-
 
 #ifndef OPAL_CONFIG_H
 #define OPAL_CONFIG_H
+
+#include "opal_config_top.h"
+
 ])
 AH_BOTTOM([
 #include "opal_config_bottom.h"

opal/include/opal_config_bottom.h

@@ -10,7 +10,7 @@
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
  * Copyright (c) 2009      Sun Microsystems, Inc.  All rights reserved.
- * Copyright (c) 2009      Cisco Systems, Inc.  All rights reserved.
+ * Copyright (c) 2009-2011 Cisco Systems, Inc.  All rights reserved.
  * $COPYRIGHT$
  * 
  * Additional copyrights may follow
@@ -618,4 +618,23 @@ static inline uint16_t ntohs(uint16_t netvar) { return netvar; }
 #define restrict
 #endif
 
+#else
+
+/* For a similar reason to what is listed in opal_config_top.h, we
+   want to protect others from the autoconf/automake-generated
+   PACKAGE_<foo> macros in opal_config.h.  We can't put these undef's
+   directly in opal_config.h because they'll be turned into #defines'
+   via autoconf.  
+
+   So put them here in case any only else includes OMPI/ORTE/OPAL's
+   config.h files. */
+
+#undef PACKAGE_BUGREPORT
+#undef PACKAGE_NAME
+#undef PACKAGE_STRING
+#undef PACKAGE_TARNAME
+#undef PACKAGE_VERSION
+#undef PACKAGE_URL
+#undef HAVE_CONFIG_H
+
 #endif /* OMPI_BUILDING */

opal/include/opal_config_top.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2011 Cisco Systems, Inc.  All rights reserved.
+ * $COPYRIGHT$
+ * 
+ * Additional copyrights may follow
+ * 
+ * $HEADER$
+ *
+ * This file is included at the top of opal_config.h, and is
+ * therefore a) before all the #define's that were output from
+ * configure, and b) included in most/all files in Open MPI.
+ *
+ * Since this file is *only* ever included by opal_config.h, and
+ * opal_config.h already has #ifndef/#endif protection, there is no
+ * need to #ifndef/#endif protection here.
+ */
+
+#ifndef OPAL_CONFIG_H 
+#error "opal_config_top.h should only be included from opal_config.h"
+#endif
+
+/* The only purpose of this file is to undef the PACKAGE_<foo> macros
+   that are put in by autoconf/automake projects.  Specifically, if
+   you include a .h file from another project that defines these
+   macros (e.g., gmp.h) and then include OMPI/ORTE/OPAL's config.h,
+   you'll get a preprocessor conflict.  So put these undef's here to
+   protect us from other package's PACKAGE_<foo> macros.  
+
+   Note that we can't put them directly in opal_config.h (e.g., via
+   AH_TOP) because they will be turned into #define's by autoconf. */
+
+#undef PACKAGE_BUGREPORT
+#undef PACKAGE_NAME
+#undef PACKAGE_STRING
+#undef PACKAGE_TARNAME
+#undef PACKAGE_VERSION
+#undef PACKAGE_URL
+#undef HAVE_CONFIG_H