linux/scripts/Makefile.extrawarn

1 # SPDX-License-Identifier: GPL-2.0
10 KBUILD_CFLAGS += -Wall
11 KBUILD_CFLAGS += -Wundef
12 KBUILD_CFLAGS += -Werror=implicit-function-declaration
13 KBUILD_CFLAGS += -Werror=implicit-int
14 KBUILD_CFLAGS += -Werror=return-type
15 KBUILD_CFLAGS += -Werror=strict-prototypes
16 KBUILD_CFLAGS += -Wno-format-security
17 KBUILD_CFLAGS += -Wno-trigraphs
18 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
19 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
22 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
25 KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
26 KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
27 KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
30 # The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
31 KBUILD_CFLAGS += -Wno-gnu
35 KBUILD_CFLAGS += -Wno-main
39 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
40 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
41 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
44 KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
47 KBUILD_CFLAGS += -Wvla
50 KBUILD_CFLAGS += -Wno-pointer-sign
54 # globally built with -Wcast-function-type.
55 KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
59 # -Wno-alloc-size-larger-than would normally be used here, earlier versions
61 # warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
68 KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
69 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
71 # Prohibit date/time macros, which would make the build non-deterministic
72 KBUILD_CFLAGS += -Werror=date-time
75 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
78 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
81 KBUILD_CFLAGS += $(call cc-option,-Wenum-conversion)
93 # W=1 - warnings which may be relevant and do not occur too often
97 KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
98 KBUILD_CFLAGS += -Wmissing-declarations
99 KBUILD_CFLAGS += $(call cc-option, -Wrestrict)
100 KBUILD_CFLAGS += -Wmissing-format-attribute
101 KBUILD_CFLAGS += -Wmissing-prototypes
102 KBUILD_CFLAGS += -Wold-style-definition
103 KBUILD_CFLAGS += -Wmissing-include-dirs
104 KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
105 KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
106 KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
107 KBUILD_CFLAGS += $(call cc-option, -Wformat-overflow)
108 KBUILD_CFLAGS += $(call cc-option, -Wformat-truncation)
109 KBUILD_CFLAGS += $(call cc-option, -Wstringop-overflow)
110 KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
112 KBUILD_CPPFLAGS += -Wundef
113 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
118 # Suppress them by using -Wno... except for W=1.
119 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
120 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
121 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
122 KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
123 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
124 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
125 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
126 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
129 # Clang before clang-16 would warn on default argument promotions.
130 ifneq ($(call clang-min-version, 160000),y)
131 # Disable -Wformat
132 KBUILD_CFLAGS += -Wno-format
133 # Then re-enable flags that were part of the -Wformat group that aren't
135 KBUILD_CFLAGS += -Wformat-extra-args -Wformat-invalid-specifier
136 KBUILD_CFLAGS += -Wformat-zero-length -Wnonnull
137 # Requires clang-12+.
138 ifeq ($(call clang-min-version, 120000),y)
139 KBUILD_CFLAGS += -Wformat-insufficient-args
142 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
143 KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare
144 KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access)
145 KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict)
146 KBUILD_CFLAGS += -Wno-enum-compare-conditional
152 # W=2 - warnings which occur quite often but may still be relevant
156 KBUILD_CFLAGS += -Wdisabled-optimization
157 KBUILD_CFLAGS += -Wshadow
158 KBUILD_CFLAGS += $(call cc-option, -Wlogical-op)
159 KBUILD_CFLAGS += -Wmissing-field-initializers
160 KBUILD_CFLAGS += -Wtype-limits
161 KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized)
162 KBUILD_CFLAGS += $(call cc-option, -Wunused-macros)
165 KBUILD_CFLAGS += -Winitializer-overrides
168 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN2
172 # The following turn off the warnings enabled by -Wextra
173 KBUILD_CFLAGS += -Wno-missing-field-initializers
174 KBUILD_CFLAGS += -Wno-type-limits
175 KBUILD_CFLAGS += -Wno-shift-negative-value
178 KBUILD_CFLAGS += -Wno-enum-enum-conversion
182 KBUILD_CFLAGS += -Wno-initializer-overrides
184 KBUILD_CFLAGS += -Wno-maybe-uninitialized
190 # W=3 - more obscure warnings, can most likely be ignored
194 KBUILD_CFLAGS += -Wbad-function-cast
195 KBUILD_CFLAGS += -Wcast-align
196 KBUILD_CFLAGS += -Wcast-qual
197 KBUILD_CFLAGS += -Wconversion
198 KBUILD_CFLAGS += -Wpacked
199 KBUILD_CFLAGS += -Wpadded
200 KBUILD_CFLAGS += -Wpointer-arith
201 KBUILD_CFLAGS += -Wredundant-decls
202 KBUILD_CFLAGS += -Wsign-compare
203 KBUILD_CFLAGS += -Wswitch-default
204 KBUILD_CFLAGS += $(call cc-option, -Wpacked-bitfield-compat)
206 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN3
210 # The following turn off the warnings enabled by -Wextra
211 KBUILD_CFLAGS += -Wno-sign-compare
216 # W=e - error out on warnings
220 KBUILD_CFLAGS += -Werror