1 # SPDX-License-Identifier: GPL-2.0
2 # ==========================================================================
6 # W=1 - warnings that may be relevant and does not occur too often
7 # W=2 - warnings that occur quite often but may still be relevant
8 # W=3 - the more obscure warnings, can most likely be ignored
10 # $(call cc-option, -W...) handles gcc -W.. options which
11 # are not supported by all versions of the compiler
12 # ==========================================================================
14 KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
16 ifeq ("$(origin W)", "command line")
17 export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
20 ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
23 warning-1 := -Wextra -Wunused -Wno-unused-parameter
24 warning-1 += -Wmissing-declarations
25 warning-1 += -Wmissing-format-attribute
26 warning-1 += $(call cc-option, -Wmissing-prototypes)
27 warning-1 += -Wold-style-definition
28 warning-1 += $(call cc-option, -Wmissing-include-dirs)
29 warning-1 += $(call cc-option, -Wunused-but-set-variable)
30 warning-1 += $(call cc-option, -Wunused-const-variable)
31 warning-1 += $(call cc-option, -Wpacked-not-aligned)
32 warning-1 += $(call cc-option, -Wstringop-truncation)
33 warning-1 += $(call cc-disable-warning, missing-field-initializers)
34 warning-1 += $(call cc-disable-warning, sign-compare)
36 warning-2 := -Waggregate-return
37 warning-2 += -Wcast-align
38 warning-2 += -Wdisabled-optimization
39 warning-2 += -Wnested-externs
41 warning-2 += $(call cc-option, -Wlogical-op)
42 warning-2 += $(call cc-option, -Wmissing-field-initializers)
43 warning-2 += $(call cc-option, -Wsign-compare)
44 warning-2 += $(call cc-option, -Wmaybe-uninitialized)
45 warning-2 += $(call cc-option, -Wunused-macros)
47 warning-3 := -Wbad-function-cast
48 warning-3 += -Wcast-qual
49 warning-3 += -Wconversion
52 warning-3 += -Wpointer-arith
53 warning-3 += -Wredundant-decls
54 warning-3 += -Wswitch-default
55 warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
57 warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
58 warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
59 warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
61 ifeq ("$(strip $(warning))","")
62 $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
65 KBUILD_CFLAGS += $(warning)
68 ifdef CONFIG_CC_IS_CLANG
69 KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides)
70 KBUILD_CFLAGS += $(call cc-disable-warning, unused-value)
71 KBUILD_CFLAGS += $(call cc-disable-warning, format)
72 KBUILD_CFLAGS += $(call cc-disable-warning, sign-compare)
73 KBUILD_CFLAGS += $(call cc-disable-warning, format-zero-length)
74 KBUILD_CFLAGS += $(call cc-disable-warning, uninitialized)