summaryrefslogtreecommitdiff
path: root/scripts/Makefile.extrawarn
diff options
context:
space:
mode:
Diffstat (limited to 'scripts/Makefile.extrawarn')
-rw-r--r--scripts/Makefile.extrawarn92
1 files changed, 54 insertions, 38 deletions
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 3ce5d503a6da..dca175fffcab 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -8,6 +8,7 @@
# Default set of warnings, always enabled
KBUILD_CFLAGS += -Wall
+KBUILD_CFLAGS += -Wextra
KBUILD_CFLAGS += -Wundef
KBUILD_CFLAGS += -Werror=implicit-function-declaration
KBUILD_CFLAGS += -Werror=implicit-int
@@ -15,8 +16,8 @@ KBUILD_CFLAGS += -Werror=return-type
KBUILD_CFLAGS += -Werror=strict-prototypes
KBUILD_CFLAGS += -Wno-format-security
KBUILD_CFLAGS += -Wno-trigraphs
-KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
-KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
+KBUILD_CFLAGS += $(call cc-option, -Wno-frame-address)
+KBUILD_CFLAGS += $(call cc-option, -Wno-address-of-packed-member)
KBUILD_CFLAGS += -Wmissing-declarations
KBUILD_CFLAGS += -Wmissing-prototypes
@@ -31,22 +32,39 @@ KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
ifdef CONFIG_CC_IS_CLANG
# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
KBUILD_CFLAGS += -Wno-gnu
+
+# Clang checks for overflow/truncation with '%p', while GCC does not:
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111219
+KBUILD_CFLAGS += $(call cc-option, -Wno-format-overflow-non-kprintf)
+KBUILD_CFLAGS += $(call cc-option, -Wno-format-truncation-non-kprintf)
+
+# Clang may emit a warning when a const variable, such as the dummy variables
+# in typecheck(), or const member of an aggregate type are not initialized,
+# which can result in unexpected behavior. However, in many audited cases of
+# the "field" variant of the warning, this is intentional because the field is
+# never used within a particular call path, the field is within a union with
+# other non-const members, or the containing object is not const so the field
+# can be modified via memcpy() / memset(). While the variable warning also gets
+# disabled with this same switch, there should not be too much coverage lost
+# because -Wuninitialized will still flag when an uninitialized const variable
+# is used.
+KBUILD_CFLAGS += $(call cc-option, -Wno-default-const-init-unsafe)
else
# gcc inanely warns about local variables called 'main'
KBUILD_CFLAGS += -Wno-main
endif
-# These warnings generated too much noise in a regular build.
-# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
-
# These result in bogus false positives
-KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
+KBUILD_CFLAGS += $(call cc-option, -Wno-dangling-pointer)
-# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
-KBUILD_CFLAGS += -Wvla
+# Stack Variable Length Arrays (VLAs) must not be used in the kernel.
+# Function array parameters should, however, be usable, but -Wvla will
+# warn for those. Clang has no way yet to distinguish between the VLA
+# types, so depend on GCC for now to keep stack VLAs out of the tree.
+# https://github.com/llvm/llvm-project/issues/57098
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98217
+KBUILD_CFLAGS += $(call cc-option,-Wvla-larger-than=1)
# disable pointer signed / unsigned warnings in gcc 4.0
KBUILD_CFLAGS += -Wno-pointer-sign
@@ -56,6 +74,13 @@ KBUILD_CFLAGS += -Wno-pointer-sign
# globally built with -Wcast-function-type.
KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
+# Currently, disable -Wstringop-overflow for GCC 11, globally.
+KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
+KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
+
+# Currently, disable -Wunterminated-string-initialization as broken
+KBUILD_CFLAGS += $(call cc-option, -Wno-unterminated-string-initialization)
+
# The allocators already balk at large sizes, so silence the compiler
# warnings for bounds checks involving those possible values. While
# -Wno-alloc-size-larger-than would normally be used here, earlier versions
@@ -82,22 +107,16 @@ KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
# Warn if there is an enum types mismatch
KBUILD_CFLAGS += $(call cc-option,-Wenum-conversion)
+KBUILD_CFLAGS += -Wunused
+
#
# W=1 - warnings which may be relevant and do not occur too often
#
ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),)
-KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
-KBUILD_CFLAGS += $(call cc-option, -Wrestrict)
KBUILD_CFLAGS += -Wmissing-format-attribute
-KBUILD_CFLAGS += -Wold-style-definition
KBUILD_CFLAGS += -Wmissing-include-dirs
-KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
-KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
-KBUILD_CFLAGS += $(call cc-option, -Wformat-overflow)
-KBUILD_CFLAGS += $(call cc-option, -Wformat-truncation)
-KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
KBUILD_CPPFLAGS += -Wundef
KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
@@ -106,13 +125,16 @@ else
# Some diagnostics enabled by default are noisy.
# Suppress them by using -Wno... except for W=1.
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
-KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
-KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
-KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
-KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
-KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
+KBUILD_CFLAGS += $(call cc-option, -Wno-unused-but-set-variable)
+KBUILD_CFLAGS += $(call cc-option, -Wno-unused-const-variable)
+KBUILD_CFLAGS += $(call cc-option, -Wno-packed-not-aligned)
+KBUILD_CFLAGS += $(call cc-option, -Wno-format-overflow)
+ifdef CONFIG_CC_IS_GCC
+KBUILD_CFLAGS += $(call cc-option, -Wno-format-truncation)
+endif
+KBUILD_CFLAGS += $(call cc-option, -Wno-stringop-truncation)
+
+KBUILD_CFLAGS += -Wno-override-init # alias for -Wno-initializer-overrides in clang
ifdef CONFIG_CC_IS_CLANG
# Clang before clang-16 would warn on default argument promotions.
@@ -128,12 +150,10 @@ ifeq ($(call clang-min-version, 120000),y)
KBUILD_CFLAGS += -Wformat-insufficient-args
endif
endif
-KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
+KBUILD_CFLAGS += $(call cc-option, -Wno-pointer-to-enum-cast)
KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare
-KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access)
-KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict)
+KBUILD_CFLAGS += $(call cc-option, -Wno-unaligned-access)
KBUILD_CFLAGS += -Wno-enum-compare-conditional
-KBUILD_CFLAGS += -Wno-enum-enum-conversion
endif
endif
@@ -146,15 +166,8 @@ ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),)
KBUILD_CFLAGS += -Wdisabled-optimization
KBUILD_CFLAGS += -Wshadow
KBUILD_CFLAGS += $(call cc-option, -Wlogical-op)
-KBUILD_CFLAGS += -Wmissing-field-initializers
-KBUILD_CFLAGS += -Wtype-limits
-KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized)
KBUILD_CFLAGS += $(call cc-option, -Wunused-macros)
-ifdef CONFIG_CC_IS_CLANG
-KBUILD_CFLAGS += -Winitializer-overrides
-endif
-
KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN2
else
@@ -165,8 +178,10 @@ KBUILD_CFLAGS += -Wno-type-limits
KBUILD_CFLAGS += -Wno-shift-negative-value
ifdef CONFIG_CC_IS_CLANG
-KBUILD_CFLAGS += -Wno-initializer-overrides
-else
+KBUILD_CFLAGS += -Wno-enum-enum-conversion
+endif
+
+ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS += -Wno-maybe-uninitialized
endif
@@ -194,6 +209,7 @@ else
# The following turn off the warnings enabled by -Wextra
KBUILD_CFLAGS += -Wno-sign-compare
+KBUILD_CFLAGS += -Wno-unused-parameter
endif