diff --git a/src/google/protobuf/stubs/platform_macros.h b/src/google/protobuf/stubs/platform_macros.h
index 1705b4162d..4cc46df453 100644
--- a/src/google/protobuf/stubs/platform_macros.h
+++ b/src/google/protobuf/stubs/platform_macros.h
@@ -62,9 +62,6 @@
 #endif
 #elif defined(__pnacl__)
 #define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(__ppc__)
-#define GOOGLE_PROTOBUF_ARCH_PPC 1
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
 #elif defined(__GNUC__) && \
  (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4))
 // We fallback to the generic GCC >= 4.7 implementation in atomicops.h