diff --git a/pb.h b/pb.h
index 174a84b..52d24de 100644
--- a/pb.h
+++ b/pb.h
@@ -122,6 +122,11 @@
 #define PB_STATIC_ASSERT_MSG(MSG, LINE, COUNTER) PB_STATIC_ASSERT_MSG_(MSG, LINE, COUNTER)
 #define PB_STATIC_ASSERT_MSG_(MSG, LINE, COUNTER) pb_static_assertion_##MSG##LINE##COUNTER
 #endif
+#ifndef STATIC_ASSERT
+#define STATIC_ASSERT PB_STATIC_ASSERT
+#define STATIC_ASSERT_MSG PB_STATIC_ASSERT_MSG
+#define STATIC_ASSERT_MSG_ PB_STATIC_ASSERT_MSG_
+#endif
 #else
 #define PB_STATIC_ASSERT(COND,MSG)
 #endif
@@ -526,6 +531,7 @@ struct pb_extension_s {
         PB_ ## rules ## _ ## allocation(tag, message, field, \
         PB_DATAOFFSET_ ## placement(message, field, prevfield), \
         PB_LTYPE_MAP_ ## type, ptr)
+#define PB_FIELD2 PB_FIELD
 
 /* Field description for repeated static fixed count fields.*/
 #define PB_REPEATED_FIXED_COUNT(tag, type, placement, message, field, prevfield, ptr) \
-- 
2.18.0.345.g5c9ce644c3-goog