1# SPDX-License-Identifier: GPL-2.0 2# ========================================================================== 3# make W=... settings 4# 5# There are three warning groups enabled by W=1, W=2, W=3. 6# They are independent, and can be combined like W=12 or W=123. 7# ========================================================================== 8 9KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned) 10 11# backward compatibility 12KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS) 13 14ifeq ("$(origin W)", "command line") 15 KBUILD_EXTRA_WARN := $(W) 16endif 17 18export KBUILD_EXTRA_WARN 19 20# 21# W=1 - warnings which may be relevant and do not occur too often 22# 23ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) 24 25KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter 26KBUILD_CFLAGS += -Wmissing-declarations 27KBUILD_CFLAGS += -Wmissing-format-attribute 28KBUILD_CFLAGS += -Wmissing-prototypes 29KBUILD_CFLAGS += -Wold-style-definition 30KBUILD_CFLAGS += -Wmissing-include-dirs 31KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable) 32KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable) 33KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned) 34KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation) 35# The following turn off the warnings enabled by -Wextra 36KBUILD_CFLAGS += -Wno-missing-field-initializers 37KBUILD_CFLAGS += -Wno-sign-compare 38 39KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1 40 41else 42 43# Some diagnostics enabled by default are noisy. 44# Suppress them by using -Wno... except for W=1. 45 46ifdef CONFIG_CC_IS_CLANG 47KBUILD_CFLAGS += -Wno-initializer-overrides 48KBUILD_CFLAGS += -Wno-format 49KBUILD_CFLAGS += -Wno-sign-compare 50KBUILD_CFLAGS += -Wno-format-zero-length 51endif 52 53endif 54 55# 56# W=2 - warnings which occur quite often but may still be relevant 57# 58ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),) 59 60KBUILD_CFLAGS += -Wcast-align 61KBUILD_CFLAGS += -Wdisabled-optimization 62KBUILD_CFLAGS += -Wnested-externs 63KBUILD_CFLAGS += -Wshadow 64KBUILD_CFLAGS += $(call cc-option, -Wlogical-op) 65KBUILD_CFLAGS += -Wmissing-field-initializers 66KBUILD_CFLAGS += -Wsign-compare 67KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized) 68KBUILD_CFLAGS += $(call cc-option, -Wunused-macros) 69 70KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN2 71 72endif 73 74# 75# W=3 - more obscure warnings, can most likely be ignored 76# 77ifneq ($(findstring 3, $(KBUILD_EXTRA_WARN)),) 78 79KBUILD_CFLAGS += -Wbad-function-cast 80KBUILD_CFLAGS += -Wcast-qual 81KBUILD_CFLAGS += -Wconversion 82KBUILD_CFLAGS += -Wpacked 83KBUILD_CFLAGS += -Wpadded 84KBUILD_CFLAGS += -Wpointer-arith 85KBUILD_CFLAGS += -Wredundant-decls 86KBUILD_CFLAGS += -Wswitch-default 87KBUILD_CFLAGS += $(call cc-option, -Wpacked-bitfield-compat) 88 89KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN3 90 91endif 92