Re: [PATCH V2 2/2] BaseTools: Factorize GCC flags

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

Reviewed-by: Bob Feng<bob.c.feng@intel.com>

-----Original Message-----
From: PierreGondois <pierre.gondois@arm.com> 
Sent: Tuesday, July 7, 2020 4:35 PM
To: devel@edk2.groups.io
Cc: Pierre Gondois <Pierre.Gondois@arm.com>; Feng, Bob C <bob.c.feng@intel.com>; Gao, Liming <liming.gao@intel.com>; tomas.pilar@arm.com; nd@arm.com
Subject: [PATCH V2 2/2] BaseTools: Factorize GCC flags

From: Pierre Gondois <pierre.gondois@arm.com>

GCC48_ALL_CC_FLAGS has no dependency on GCC_ALL_CC_FLAGS.
By definition, there should be such dependency.

The outcomes of this patch is that GCC48_ALL_CC_FLAGS and other dependent configurations will inherit from the additional "-Os" flag.
The "-Os" flag optimizes a build in size, not breaking any build. In a gcc command line, the last optimization flag has precedence. This means that this "-Os" flag will be overriden by a more specific optimization configuration, provided that this more specific flag is appended at the end of the CC_FLAGS.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Suggested-by: Tomas Pilar <Tomas.Pilar@arm.com>
---

The changes can be seen at: https://github.com/PierreARM/edk2/commits/831_Add_gcc_flag_warning_v2

Notes:
    v2:
     - Make GCC48_ALL_CC_FLAGS dependent on
       GCC_ALL_CC_FLAGS. [Tomas]

 BaseTools/Conf/tools_def.template | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/BaseTools/Conf/tools_def.template b/BaseTools/Conf/tools_def.template
index 397b011ba38f97f81f314f8641ac8bb95d5a2197..a1fd27b1adba8769949b7d628d7fbed49fe24267 100755
--- a/BaseTools/Conf/tools_def.template
+++ b/BaseTools/Conf/tools_def.template
@@ -1952,7 +1952,7 @@ DEFINE GCC_RISCV64_RC_FLAGS        = -I binary -O elf64-littleriscv   -B riscv
 # GCC Build Flag for included header file list generation
 DEFINE GCC_DEPS_FLAGS              = -MMD -MF $@.deps
 
-DEFINE GCC48_ALL_CC_FLAGS            = -g -fshort-wchar -fno-builtin -fno-strict-aliasing -Wall -Werror -Wno-array-bounds -ffunction-sections -fdata-sections -include AutoGen.h -fno-common -DSTRING_ARRAY_NAME=$(BASE_NAME)Strings
+DEFINE GCC48_ALL_CC_FLAGS            = DEF(GCC_ALL_CC_FLAGS) -ffunction-sections -fdata-sections -DSTRING_ARRAY_NAME=$(BASE_NAME)Strings
 DEFINE GCC48_IA32_X64_DLINK_COMMON   = -nostdlib -Wl,-n,-q,--gc-sections -z common-page-size=0x20
 DEFINE GCC48_IA32_CC_FLAGS           = DEF(GCC48_ALL_CC_FLAGS) -m32 -march=i586 -malign-double -fno-stack-protector -D EFI32 -fno-asynchronous-unwind-tables -Wno-address
 DEFINE GCC48_X64_CC_FLAGS            = DEF(GCC48_ALL_CC_FLAGS) -m64 -fno-stack-protector "-DEFIAPI=__attribute__((ms_abi))" -maccumulate-outgoing-args -mno-red-zone -Wno-address -mcmodel=small -fpie -fno-asynchronous-unwind-tables -Wno-address
--
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'