diff --git a/BaseTools/Source/C/Makefiles/header.makefile b/BaseTools/Source/C/Makefiles/header.makefile
index f2041f8f03..821d114e78 100644
--- a/BaseTools/Source/C/Makefiles/header.makefile
+++ b/BaseTools/Source/C/Makefiles/header.makefile
@@ -44,12 +44,12 @@ ARCH_INCLUDE = -I $(MAKEROOT)/Include/AArch64/
 endif
 
 INCLUDE = $(TOOL_INCLUDE) -I $(MAKEROOT) -I $(MAKEROOT)/Include/Common -I $(MAKEROOT)/Include/ -I $(MAKEROOT)/Include/IndustryStandard -I $(MAKEROOT)/Common/ -I .. -I . $(ARCH_INCLUDE) 
-BUILD_CPPFLAGS = $(INCLUDE)
+BUILD_CPPFLAGS = $(INCLUDE) -O2
 ifeq ($(DARWIN),Darwin)
 # assume clang or clang compatible flags on OS X
-BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -Wno-self-assign -nostdlib -c -g
+BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -Wno-self-assign -Wno-unused-result -nostdlib -c -g
 else
-BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -nostdlib -c -g
+BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -Wno-unused-result -nostdlib -c -g
 endif
 BUILD_LFLAGS =
 BUILD_CXXFLAGS =