diff --git a/Makefile b/Makefile
index 8d27cc80..09ec302d 100644
--- a/Makefile
+++ b/Makefile
@@ -116,7 +116,10 @@ CXXFLAGS=$(OPT) $(LLVM_CXXFLAGS) -I. -Iobjs/ -I$(CLANG_INCLUDE)  \
 	$(LLVM_VERSION_DEF) \
 	-Wall \
 	-DBUILD_DATE="\"$(BUILD_DATE)\"" -DBUILD_VERSION="\"$(BUILD_VERSION)\"" \
-	-Werror -Wno-sign-compare
+	-Wno-sign-compare
+ifneq ($(LLVM_VERSION),LLVM_3_1)
+	CXXFLAGS+=-Werror
+endif
 ifneq ($(ARM_ENABLED), 0)
     CXXFLAGS+=-DISPC_ARM_ENABLED
 endif