diff -rup ./include/dwarf.h ../../libunwind/libunwind-1.1/include/dwarf.h
--- ./include/dwarf.h	2012-10-06 00:54:38.000000000 -0400
+++ ../../libunwind/libunwind-1.1/include/dwarf.h	2013-10-03 17:14:08.925192159 -0400
@@ -26,6 +26,12 @@ WITH THE SOFTWARE OR THE USE OR OTHER DE
 #ifndef dwarf_h
 #define dwarf_h
 
+/* we need to pull config.h so that, minimally, we pick up the setting  */
+/* for CONFIG_MSABI_SUPPORT.                                            */
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <libunwind.h>
 
 struct dwarf_cursor;	/* forward-declaration */