Re: Enable -Wstrict-prototypes and -Wold-style-definition by default

Hi,

On Fri, Mar 27, 2026 at 08:38:45AM +0100, Peter Eisentraut wrote:
> The first three patches have been committed.
> 
> On 24.03.26 08:16, Bertrand Drouvot wrote:
> > 0004:
> > 
> > --- a/meson.build
> > +++ b/meson.build
> > @@ -2199,6 +2199,7 @@ unroll_loops_cflags = cc.get_supported_arguments(['-funroll-loops'])
> >   common_warning_flags = [
> >     '-Wmissing-prototypes',
> > +  '-Wold-style-declaration',
> > 
> > Nit, what about adding it with (as the comment is also accurate for the new one)?
> > 
> > "
> > # These are C-only flags, supported in all C11-capable GCC/Clang versions.
> > cflags_warn += cc.get_supported_arguments(['-Wstrict-prototypes', '-Wold-style-definition'])
> > "
> 
> Yeah, makes sense to collect the C-only flags together.  But now that I'm
> looking at this again, the comment "supported in all C11-capable GCC/Clang
> versions" is not relevant here, it was only relevant in configure.ac because
> there we don't actually test for these flags but require them without
> testing. 

Right, it was a bit misleading.

> What do you think about the attached patch, which reorganizes this
> a bit more?

+# C-only warnings
+c_warning_flags = [
+  '-Wmissing-prototypes',
+  '-Wold-style-declaration',
+  '-Wold-style-definition',
+  '-Wstrict-prototypes',
+]

That looks ok but I wonder if we should also add '-Werror=vla' to it (
and remove it from common_warning_flags) to be in sync with what configure.ac
is doing:

"
  PGAC_PROG_CC_CFLAGS_OPT([-Werror=vla])
  # -Wvla is not applicable for C++
"

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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