--- mozilla/config/config.mk.fix	2016-06-20 15:03:19.000000000 +0300

+++ mozilla/config/config.mk	2016-06-20 15:03:24.000000000 +0300

@@ -345,8 +345,10 @@ endif # WINNT && (MOS_PROFILE_GENERATE ^

 ifdef CLANG_CL

 ALLOW_COMPILER_WARNINGS=1

 endif # CLANG_CL

+ALLOW_COMPILER_WARNINGS=1

+

 # Use warnings-as-errors if ALLOW_COMPILER_WARNINGS is not set to 1 (which

 # includes the case where it's undefined).

 ifneq (1,$(ALLOW_COMPILER_WARNINGS))

 CXXFLAGS += $(WARNINGS_AS_ERRORS)