[Patch] BaseTools: Add GCC flags to Basetool build.

["Bob Feng" <bob.c.feng@intel.com>]

BZ:https://bugzilla.tianocore.org/show_bug.cgi?id=1764

Some compiler flags restrict the compiler from making
arbitrary decisions while handling undefined C/C++ behaviors.
Therefore they can be used to fix some issues caused by undefined behavior.

For example, for GCC, the following flags are available:
-fno-strict-overflow tells the compiler NOT to assume
that signed overflow does not occur.
-fno-delete-null-pointer-checks tells
the compiler NOT to assume that null pointer deference does not exist.
-fwrapv tells the compiler that signed overflow always wraps.

This patch is going to add these 3 build options to
BaseTool GCC build option.

Signed-off-by: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
---
 BaseTools/Source/C/Makefiles/header.makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/BaseTools/Source/C/Makefiles/header.makefile b/BaseTools/Source/C/Makefiles/header.makefile
index 90fb3453ad..f1aed62769 100644
--- a/BaseTools/Source/C/Makefiles/header.makefile
+++ b/BaseTools/Source/C/Makefiles/header.makefile
@@ -68,11 +68,11 @@ BUILD_OPTFLAGS = -O2 $(EXTRA_OPTFLAGS)
 
 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 -Wno-unused-result -nostdlib -g
 else
-BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -Wno-stringop-truncation -Wno-restrict -Wno-unused-result -nostdlib -g
+BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-deprecated-declarations -Wno-stringop-truncation -Wno-restrict -Wno-unused-result -nostdlib -g -fwrapv -fno-delete-null-pointer-checks -fno-strict-overflow
 endif
 BUILD_LFLAGS =
 BUILD_CXXFLAGS = -Wno-unused-result
 
 ifeq ($(HOST_ARCH), IA32)
-- 
2.20.1.windows.1