Need to work around issue with fixed size printing when including METIS

configure.ac

@@ -457,6 +457,14 @@ AC_SUBST([METIS_LIBS])
 AC_SUBST([METIS_INCS])
 AM_CONDITIONAL([HAVEMETIS],[test -n "$METIS_LIBS"])
 
+# METIS fixed width integer printing can require this, so define. Only needed
+# for some non C99 compilers, i.e. C++ pre C++11.
+AH_VERBATIM([__STDC_FORMAT_MACROS],
+            [/* Needed to get PRIxxx macros from stdint.h when not using C99 */
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS 1
+#endif])
+
 # Check for grackle. 
 have_grackle="no"
 AC_ARG_WITH([grackle],