scripts/Makefile.extrawarn

   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
   9 KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
  10
  11 # backward compatibility
  12 KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
  13
  14 ifeq ("$(origin W)", "command line")
  15   KBUILD_EXTRA_WARN := $(W)
  16 endif
  17
  18 export KBUILD_EXTRA_WARN
  19
  20 #
  21 # W=1 - warnings which may be relevant and do not occur too often
  22 #
  23 ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),)
  24
  25 KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
  26 KBUILD_CFLAGS += -Wmissing-declarations
  27 KBUILD_CFLAGS += -Wmissing-format-attribute
  28 KBUILD_CFLAGS += -Wmissing-prototypes
  29 KBUILD_CFLAGS += -Wold-style-definition
  30 KBUILD_CFLAGS += -Wmissing-include-dirs
  31 KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
  32 KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
  33 KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
  34 KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
  35 # The following turn off the warnings enabled by -Wextra
  36 KBUILD_CFLAGS += -Wno-missing-field-initializers
  37 KBUILD_CFLAGS += -Wno-sign-compare
  38 KBUILD_CFLAGS += -Wno-type-limits
  39
  40 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
  41
  42 else
  43
  44 # Some diagnostics enabled by default are noisy.
  45 # Suppress them by using -Wno... except for W=1.
  46
  47 ifdef CONFIG_CC_IS_CLANG
  48 KBUILD_CFLAGS += -Wno-initializer-overrides
  49 KBUILD_CFLAGS += -Wno-format
  50 KBUILD_CFLAGS += -Wno-sign-compare
  51 KBUILD_CFLAGS += -Wno-format-zero-length
  52 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
  53 KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare
  54 KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access)
  55 KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict)
  56 endif
  57
  58 endif
  59
  60 #
  61 # W=2 - warnings which occur quite often but may still be relevant
  62 #
  63 ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),)
  64
  65 KBUILD_CFLAGS += -Wdisabled-optimization
  66 KBUILD_CFLAGS += -Wshadow
  67 KBUILD_CFLAGS += $(call cc-option, -Wlogical-op)
  68 KBUILD_CFLAGS += -Wmissing-field-initializers
  69 KBUILD_CFLAGS += -Wtype-limits
  70 KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized)
  71 KBUILD_CFLAGS += $(call cc-option, -Wunused-macros)
  72
  73 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN2
  74
  75 endif
  76
  77 #
  78 # W=3 - more obscure warnings, can most likely be ignored
  79 #
  80 ifneq ($(findstring 3, $(KBUILD_EXTRA_WARN)),)
  81
  82 KBUILD_CFLAGS += -Wbad-function-cast
  83 KBUILD_CFLAGS += -Wcast-align
  84 KBUILD_CFLAGS += -Wcast-qual
  85 KBUILD_CFLAGS += -Wconversion
  86 KBUILD_CFLAGS += -Wpacked
  87 KBUILD_CFLAGS += -Wpadded
  88 KBUILD_CFLAGS += -Wpointer-arith
  89 KBUILD_CFLAGS += -Wredundant-decls
  90 KBUILD_CFLAGS += -Wsign-compare
  91 KBUILD_CFLAGS += -Wswitch-default
  92 KBUILD_CFLAGS += $(call cc-option, -Wpacked-bitfield-compat)
  93
  94 KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN3
  95
  96 endif