diff --git a/common/arch.h b/common/arch.h
index d3ae460e..6ae3aa1d 100644
--- a/common/arch.h
+++ b/common/arch.h
@@ -36,12 +36,27 @@
 #endif
 #endif
 
+#if !(defined(L_ENDIAN) || defined(B_ENDIAN))
+#if defined(__powerpc64__)
+# if defined(__BIG_ENDIAN__)
+#  define B_ENDIAN
+# else
+#  define L_ENDIAN
+# endif
+#endif
+#endif
+
 #if !(defined(L_ENDIAN) || defined(B_ENDIAN))
 #if defined(__sparc__) || defined(__PPC__) || defined(__ppc__) || \
     defined(__hppa__)
 #define B_ENDIAN
 #else
-#define L_ENDIAN
+# if defined(__sparc__) || defined(__PPC__) || defined(__ppc__) || \
+     defined(__hppa__)
+#  define B_ENDIAN
+# else
+#  define L_ENDIAN
+# endif
 #endif
 #endif
 #endif