On Tue, Apr 29, 2025 at 09:11:05AM +0800, Ming Lei wrote:
> On Mon, Apr 28, 2025 at 05:10:20PM -0600, Uday Shankar wrote:
> > Compiler warnings can catch bugs at compile time. They can also produce
> > annoying false positives. Due to this duality, the kernel provides
> > CONFIG_WERROR so that the developer can choose whether or not they want
> > compiler warnings to fail the build. Use this same config options to
> > control whether or not warnings in building kublk fail its build.
> >
> > Signed-off-by: Uday Shankar <ushankar@xxxxxxxxxxxxxxx>
> > ---
> > tools/testing/selftests/ublk/Makefile | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile
> > index ec4624a283bce2ebeed80509be6573c1b7a3623d..86474cfe8d03b2df3f8c9bc1a5902701a0f72f58 100644
> > --- a/tools/testing/selftests/ublk/Makefile
> > +++ b/tools/testing/selftests/ublk/Makefile
> > @@ -1,6 +1,8 @@
> > # SPDX-License-Identifier: GPL-2.0
> >
> > -CFLAGS += -O3 -Wl,-no-as-needed -Wall -I $(top_srcdir)
> > +CONFIG = $(top_srcdir)/include/config/auto.conf
> > +WERROR = $(if $(shell grep CONFIG_WERROR=y ${CONFIG}),-Werror,)
> > +CFLAGS += -O3 -Wl,-no-as-needed -Wall ${WERROR} -I $(top_srcdir)
> > LDLIBS += -lpthread -lm -luring
>
> I think it isn't good to reuse kernel CONFIG_WERROR for test code.
>
> But it can be done in the following way by passing 'WERROR=1' to make
> command line:
>
> +ifneq ($(WERROR),0)
> + CFLAGS += -Werror
> +endif
I've taken this approach in [1]. It actually passes -Werror by default,
but it gives the developer a way to disable it with
make WERROR=0 TARGETS=ublk kselftest
[1] https://lore.kernel.org/linux-block/20250429-ublk_selftests-v2-1-e970b6d9e4f4@xxxxxxxxxxxxxxx/
