Re: [PATCH] tools/libbpf: add WERROR option

[Daniel Borkmann]

On 7/5/25 12:43 PM, Sam James wrote:
> Check the 'WERROR' variable and suppress adding '-Werror' if WERROR=0.
>
> This mirrors what tools/perf and other directories in tools do to handle
> -Werror rather than adding it unconditionally.

Could you also add to the commit desc why you need it? Are there particular
warnings you specifically need to suppress when building under gentoo?

> Signed-off-by: Sam James <sam@xxxxxxxxxx>
> ---
>   tools/lib/bpf/Makefile | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index 168140f8e646..9563d37265da 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -77,10 +77,15 @@ else
>     CFLAGS := -g -O2
>   endif
>   
> +# Treat warnings as errors unless directed not to
> +ifneq ($(WERROR),0)
> +  CFLAGS += -Werror
> +endif

Should we also add sth similar to tools/bpf/bpftool/Makefile and by default
enforce with -Werror with the option to disable?

>   # Append required CFLAGS
>   override CFLAGS += -std=gnu89
>   override CFLAGS += $(EXTRA_WARNINGS) -Wno-switch-enum
> -override CFLAGS += -Werror -Wall
> +override CFLAGS += -Wall
>   override CFLAGS += $(INCLUDES)
>   override CFLAGS += -fvisibility=hidden
>   override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64