Commit 3fe617cc authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Enable '-Werror' by default for all kernel builds 



... but make it a config option so that broken environments can disable
it when required.

We really should always have a clean build, and will disable specific
over-eager warnings as required, if we can't fix them.  But while I
fairly religiously enforce that in my own tree, it doesn't get enforced
by various build robots that don't necessarily report warnings.

So this just makes '-Werror' a default compiler flag, but allows people
to disable it for their configuration if they have some particular
issues.

Occasionally, new compiler versions end up enabling new warnings, and it
can take a while before we have them fixed (or the warnings disabled if
that is what it takes), so the config option allows for that situation.

Hopefully this will mean that I get fewer pull requests that have new
warnings that were not noticed by various automation we have in place.

Knock wood.

Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent fd47ff55

Makefile

+3 −0
Original line number Diff line number Diff line
@@ -785,6 +785,9 @@ stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong 


KBUILD_CFLAGS += $(stackp-flags-y)



KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror

KBUILD_CFLAGS += $(KBUILD_CFLAGS-y)



ifdef CONFIG_CC_IS_CLANG

KBUILD_CPPFLAGS += -Qunused-arguments

# The kernel builds with '-std=gnu89' so use of GNU extensions is acceptable.

init/Kconfig

+14 −0
Original line number Diff line number Diff line
@@ -137,6 +137,20 @@ config COMPILE_TEST 
	  here. If you are a user/distributor, say N here to exclude useless

	  drivers to be distributed.



config WERROR

	bool "Compile the kernel with warnings as errors"

	default y

	help

	  A kernel build should not cause any compiler warnings, and this

	  enables the '-Werror' flag to enforce that rule by default.



	  However, if you have a new (or very old) compiler with odd and

	  unusual warnings, or you have some architecture with problems,

	  you may need to disable this config option in order to

	  successfully build the kernel.



	  If in doubt, say Y.



config UAPI_HEADER_TEST

	bool "Compile test UAPI headers"

	depends on HEADERS_INSTALL && CC_CAN_LINK