diff --git a/llvm/test/Makefile b/llvm/test/Makefile
index eac56ab215c7..9ee8f8e050c2 100644
--- a/llvm/test/Makefile
+++ b/llvm/test/Makefile
@@ -61,6 +61,7 @@ site.exp: Makefile $(LLVM_OBJ_ROOT)/Makefile.config
 	@echo 'set llvmgcc "PATH=\"$(LLVMToolDir):$(PATH)\" \"$(LLVMGCC)\""' >> site.tmp
 	@echo 'set llvmgxx "PATH=\"$(LLVMToolDir):$(PATH)\" \"$(LLVMGCC)\""' >> site.tmp
 	@echo 'set llvmgccmajvers "$(LLVMGCC_MAJVERS)"' >> site.tmp
+	@echo 'set gxxcmd "$(CXX) $(CPP.Flags) $(CXX.Flags) $(CompileCommonOpts)"' >> site.tmp
 	@echo '## All variables above are generated by configure. Do Not Edit ## ' >>site.tmp
 	@test ! -f site.exp || \
 	sed '1,/^## All variables above are.*##/ d' site.exp >> site.tmp