Merge from mainline.

Probe for flags before using them to try to help compiling with
compilers that don't support those flags.  This hopefully will help
gcc 3.X compile this code.  http://llvm.org/PR3487

llvm-svn: 64514

Author: tlattner

llvm/utils/unittest/googletest/Makefile

@@ -9,10 +9,13 @@
 
 LEVEL := ../../..
 include $(LEVEL)/Makefile.config
+NO_MISSING_FIELD_INITIALIZERS := $(shell $(CXX) -Wno-missing-field-initializers -fsyntax-only -xc /dev/null 2>/dev/null && echo -Wno-missing-field-initializers)
+NO_VAROADIC_MACROS := $(shell $(CXX) -Wno-variadic-macros -fsyntax-only -xc /dev/null 2>/dev/null && echo -Wno-variadic-macros)
+
 
 LIBRARYNAME = GoogleTest
 BUILD_ARCHIVE = 1
 CPP.Flags += -I$(LLVM_SRC_ROOT)/utils/unittest/googletest/include/
-CPP.Flags += -Wno-missing-field-initializers -Wno-variadic-macros
+CPP.Flags += $(NO_MISSING_FIELD_INITIALIZERS) $(NO_VAROADIC_MACROS)
 
 include $(LEVEL)/Makefile.common