[Patch 2/2] BaseTools: Add GCC flags to Basetool build.

[Patch 2/2] BaseTools: Add GCC flags to Basetool build.

[Bob Feng]

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-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 2 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 | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/BaseTools/Source/C/Makefiles/header.makefile b/BaseTools/Source/C/Makefiles/header.makefile
index c2397b796c..eac295b4dd 100644
--- a/BaseTools/Source/C/Makefiles/header.makefile
+++ b/BaseTools/Source/C/Makefiles/header.makefile
@@ -69,11 +69,12 @@ 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 \
+BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -fwrapv \
+-fno-delete-null-pointer-checks -Wall -Werror \
 -Wno-deprecated-declarations -Wno-stringop-truncation -Wno-restrict \
 -Wno-unused-result -nostdlib -g
 endif
 BUILD_LFLAGS =
 BUILD_CXXFLAGS = -Wno-unused-result
-- 
2.20.1.windows.1

Re: [edk2-devel] [Patch 2/2] BaseTools: Add GCC flags to Basetool build.

[Laszlo Ersek]

On 04/30/19 13:07, Bob Feng wrote:
> 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-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 2 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 | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/BaseTools/Source/C/Makefiles/header.makefile b/BaseTools/Source/C/Makefiles/header.makefile
> index c2397b796c..eac295b4dd 100644
> --- a/BaseTools/Source/C/Makefiles/header.makefile
> +++ b/BaseTools/Source/C/Makefiles/header.makefile
> @@ -69,11 +69,12 @@ 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 \
> +BUILD_CFLAGS = -MD -fshort-wchar -fno-strict-aliasing -fwrapv \
> +-fno-delete-null-pointer-checks -Wall -Werror \
>  -Wno-deprecated-declarations -Wno-stringop-truncation -Wno-restrict \
>  -Wno-unused-result -nostdlib -g
>  endif
>  BUILD_LFLAGS =
>  BUILD_CXXFLAGS = -Wno-unused-result
> 

Reviewed-by: Laszlo Ersek <lersek@redhat.com>