Re: [PATCH 1/3] selftests: ublk: kublk: build with -Werror iff CONFIG_WERROR=y

[Ming Lei <ming.lei@redhat.com>]

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@purestorage.com>
> ---
>  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



Thanks,
Ming