--- a/src/sys/memory/mem.c
+++ b/src/sys/memory/mem.c
@@ -21,6 +21,9 @@
 #include <sys/resource.h>
 #endif
 #if defined(PETSC_HAVE_SYS_PROCFS_H)
+#if defined __GNU__
+#include <mach/std_types.h>
+#endif
 /* #include <sys/int_types.h> Required if using gcc on solaris 2.6 */
 #include <sys/procfs.h>
 #endif