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 += -Wmissing-prototypes
27 warning-1 += -Wold-style-definition
28 warning-1 += -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 # The following turn off the warnings enabled by -Wextra
34 warning-1 += -Wno-missing-field-initializers
35 warning-1 += -Wno-sign-compare
37 warning-2 := -Waggregate-return
38 warning-2 += -Wcast-align
39 warning-2 += -Wdisabled-optimization
40 warning-2 += -Wnested-externs
42 warning-2 += $(call cc-option, -Wlogical-op)
43 warning-2 += -Wmissing-field-initializers
44 warning-2 += -Wsign-compare
45 warning-2 += $(call cc-option, -Wmaybe-uninitialized)
46 warning-2 += $(call cc-option, -Wunused-macros)
48 warning-3 := -Wbad-function-cast
49 warning-3 += -Wcast-qual
50 warning-3 += -Wconversion
53 warning-3 += -Wpointer-arith
54 warning-3 += -Wredundant-decls
55 warning-3 += -Wswitch-default
56 warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
58 warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
59 warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
60 warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
62 ifeq ("$(strip $(warning))","")
63 $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
66 KBUILD_CFLAGS += $(warning)
69 ifdef CONFIG_CC_IS_CLANG
70 KBUILD_CFLAGS += -Wno-initializer-overrides
71 KBUILD_CFLAGS += -Wno-unused-value
72 KBUILD_CFLAGS += -Wno-format
73 KBUILD_CFLAGS += -Wno-sign-compare
74 KBUILD_CFLAGS += -Wno-format-zero-length
75 KBUILD_CFLAGS += -Wno-uninitialized