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

[Masahiro Yamada]

On Wed, Jun 7, 2023 at 1:56 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote:
>
> 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?


This one.

https://lore.kernel.org/linux-kbuild/CAK7LNAR0uMvf+k7LPXtMjigKFPeNu5m5EhAkvk2RVRHkdjdbdg@xxxxxxxxxxxxxx/T/#m0f41f2c8fe843133ce8100088443491a51d496af


> > ---
> >
> >  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



-- 
Best Regards
Masahiro Yamada