Re: [PATCH] modpost: propagate W=1 build option to modpost

[Nick Desaulniers]

On Tue, Jun 6, 2023 at 2:42 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> "No build warning" is a strong requirement these days, so you must fix
> all issues before enabling a new warning flag.
>
> We often add a new warning to W=1 first so that the kbuild test robot
> blocks new breakages.
>
> This commit allows modpost to show extra warnings only when W=1
> (or KBUILD_EXTRA_WARN=1) is given.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>

Patch seems fine, but without anyone reading extra_warn, I'm curious
what new extra warnings you had in mind were?

> ---
>
>  scripts/Makefile.modpost | 1 +
>  scripts/mod/modpost.c    | 7 ++++++-
>  2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
> index 0980c58d8afc..074e27c0c140 100644
> --- a/scripts/Makefile.modpost
> +++ b/scripts/Makefile.modpost
> @@ -47,6 +47,7 @@ modpost-args =                                                                                \
>         $(if $(KBUILD_MODPOST_WARN),-w)                                                 \
>         $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS))                                     \
>         $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N)       \
> +       $(if $(findstring 1, $(KBUILD_EXTRA_WARN)),-W)                                  \
>         -o $@
>
>  modpost-deps := $(MODPOST)
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index d10f5bdcb753..3ea5eb2b1029 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -42,6 +42,8 @@ static bool allow_missing_ns_imports;
>
>  static bool error_occurred;
>
> +static bool extra_warn;
> +
>  /*
>   * Cut off the warnings when there are too many. This typically occurs when
>   * vmlinux is missing. ('make modules' without building vmlinux.)
> @@ -2199,7 +2201,7 @@ int main(int argc, char **argv)
>         LIST_HEAD(dump_lists);
>         struct dump_list *dl, *dl2;
>
> -       while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
> +       while ((opt = getopt(argc, argv, "ei:mnT:o:aWwENd:")) != -1) {
>                 switch (opt) {
>                 case 'e':
>                         external_module = true;
> @@ -2224,6 +2226,9 @@ int main(int argc, char **argv)
>                 case 'T':
>                         files_source = optarg;
>                         break;
> +               case 'W':
> +                       extra_warn = true;
> +                       break;
>                 case 'w':
>                         warn_unresolved = true;
>                         break;
> --
> 2.39.2
>


-- 
Thanks,
~Nick Desaulniers