xref: /linux/scripts/Makefile.extrawarn (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
1# SPDX-License-Identifier: GPL-2.0
2# ==========================================================================
3#
4# make W=... settings
5#
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
9#
10# $(call cc-option, -W...) handles gcc -W.. options which
11# are not supported by all versions of the compiler
12# ==========================================================================
13
14KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
15
16ifeq ("$(origin W)", "command line")
17  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
18endif
19
20ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
21warning-  := $(empty)
22
23warning-1 := -Wextra -Wunused -Wno-unused-parameter
24warning-1 += -Wmissing-declarations
25warning-1 += -Wmissing-format-attribute
26warning-1 += $(call cc-option, -Wmissing-prototypes)
27warning-1 += -Wold-style-definition
28warning-1 += $(call cc-option, -Wmissing-include-dirs)
29warning-1 += $(call cc-option, -Wunused-but-set-variable)
30warning-1 += $(call cc-option, -Wunused-const-variable)
31warning-1 += $(call cc-option, -Wpacked-not-aligned)
32warning-1 += $(call cc-disable-warning, missing-field-initializers)
33warning-1 += $(call cc-disable-warning, sign-compare)
34
35warning-2 := -Waggregate-return
36warning-2 += -Wcast-align
37warning-2 += -Wdisabled-optimization
38warning-2 += -Wnested-externs
39warning-2 += -Wshadow
40warning-2 += $(call cc-option, -Wlogical-op)
41warning-2 += $(call cc-option, -Wmissing-field-initializers)
42warning-2 += $(call cc-option, -Wsign-compare)
43warning-2 += $(call cc-option, -Wmaybe-uninitialized)
44warning-2 += $(call cc-option, -Wunused-macros)
45
46warning-3 := -Wbad-function-cast
47warning-3 += -Wcast-qual
48warning-3 += -Wconversion
49warning-3 += -Wpacked
50warning-3 += -Wpadded
51warning-3 += -Wpointer-arith
52warning-3 += -Wredundant-decls
53warning-3 += -Wswitch-default
54warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
55warning-3 += $(call cc-option, -Wvla)
56
57warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
58warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
59warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
60
61ifeq ("$(strip $(warning))","")
62        $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
63endif
64
65KBUILD_CFLAGS += $(warning)
66else
67
68ifeq ($(cc-name),clang)
69KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides)
70KBUILD_CFLAGS += $(call cc-disable-warning, unused-value)
71KBUILD_CFLAGS += $(call cc-disable-warning, format)
72KBUILD_CFLAGS += $(call cc-disable-warning, sign-compare)
73KBUILD_CFLAGS += $(call cc-disable-warning, format-zero-length)
74KBUILD_CFLAGS += $(call cc-disable-warning, uninitialized)
75endif
76endif
77