From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cam-smtp0.cambridge.arm.com (cam-smtp0.cambridge.arm.com [217.140.106.52]) by mx.groups.io with SMTP id smtpd.web11.17804.1593530664944548464 for ; Tue, 30 Jun 2020 08:24:25 -0700 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: arm.com, ip: 217.140.106.52, mailfrom: pierre.gondois@arm.com) Received: from E119881.Arm.com (E119881.Arm.com [10.1.197.28]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id 05UFOLWH029343; Tue, 30 Jun 2020 16:24:21 +0100 From: "PierreGondois" To: devel@edk2.groups.io Cc: Pierre Gondois , bob.c.feng@intel.com, liming.gao@intel.com, nd@arm.com Subject: [PATCH v1] BaseTools: Add gcc flag to warn on void* pointer arithmetic Date: Tue, 30 Jun 2020 16:24:16 +0100 Message-Id: <20200630152416.28240-1-pierre.gondois@arm.com> X-Mailer: git-send-email 2.16.2.windows.1 From: Pierre Gondois By default, gcc allows void* pointer arithmetic. This is a GCC extension. However: - the C reference manual states that void* pointer "cannot be operands of addition or subtraction operators". Cf s5.3.1 "Generic Pointers"; - Visual studio compiler treat such operation as an error. To prevent such pointer arithmetic, the "-Wpointer-arith" flag should be set for all GCC versions. The "-Wpointer-arith" allows to: "Warn about anything that depends on the "size of" a function type or of void. GNU C assigns these types a size of 1, for convenience in calculations with void * pointers and pointers to functions." This flag is available since GCC2.95.3 which came out in 2001. Signed-off-by: Pierre Gondois --- The changes can be seen at: https://github.com/PierreARM/edk2/commits/831_Add_gcc_flag_warning_v1 Notes: v1: - Add "-Wpointer-arith" gcc flag. [Pierre] BaseTools/Conf/tools_def.template | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/BaseTools/Conf/tools_def.template b/BaseTools/Conf/tools_def.template index 8aeb8a2a6417e41c5660cda5066f52adc8cc3089..fba71665d6ade4dad08a5a0c343f357fd413a8a4 100755 --- a/BaseTools/Conf/tools_def.template +++ b/BaseTools/Conf/tools_def.template @@ -1,7 +1,7 @@ # # Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
# Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.
-# Portions copyright (c) 2011 - 2019, ARM Ltd. All rights reserved.
+# Portions copyright (c) 2011 - 2020, ARM Ltd. All rights reserved.
# Copyright (c) 2015, Hewlett-Packard Development Company, L.P.
# (C) Copyright 2020, Hewlett Packard Enterprise Development LP
# Copyright (c) Microsoft Corporation @@ -1918,7 +1918,7 @@ NOOPT_*_*_OBJCOPY_ADDDEBUGFLAG = --add-gnu-debuglink=$(DEBUG_DIR)/$(MODULE_N *_*_*_DTCPP_PATH = DEF(DTCPP_BIN) *_*_*_DTC_PATH = DEF(DTC_BIN) -DEFINE GCC_ALL_CC_FLAGS = -g -Os -fshort-wchar -fno-builtin -fno-strict-aliasing -Wall -Werror -Wno-array-bounds -include AutoGen.h -fno-common +DEFINE GCC_ALL_CC_FLAGS = -g -Os -fshort-wchar -fno-builtin -fno-strict-aliasing -Wall -Werror -Wpointer-arith -Wno-array-bounds -include AutoGen.h -fno-common DEFINE GCC_IA32_CC_FLAGS = DEF(GCC_ALL_CC_FLAGS) -m32 -malign-double -freorder-blocks -freorder-blocks-and-partition -O2 -mno-stack-arg-probe DEFINE GCC_X64_CC_FLAGS = DEF(GCC_ALL_CC_FLAGS) -mno-red-zone -Wno-address -mno-stack-arg-probe DEFINE GCC_ARM_CC_FLAGS = DEF(GCC_ALL_CC_FLAGS) -mlittle-endian -mabi=aapcs -fno-short-enums -funsigned-char -ffunction-sections -fdata-sections -fomit-frame-pointer -Wno-address -mthumb -mfloat-abi=soft -fno-pic -fno-pie -- 'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'