Re: [PATCH] meson.build: Remove the -Wvla-larger-then flag

On Thu, May 27, 2021 at 12:49:28PM +0200, Martin Kletzander wrote: > On Thu, May 27, 2021 at 12:37:36PM +0200, Thomas Huth wrote: > > The flag has a typo in it, it's "...-than=..." and not "...-then=...", > > so this was in fact never used. Since we're also using -Wvla (without > > size), we should already get warnings about any variable length arrays > > anyway, so the additional "-Wvla-larger-than" does not make much sense > > and thus we can simply drop this. > > > > Signed-off-by: Thomas Huth <thuth(a)redhat.com&gt; > > --- > > meson.build | 1 - > > 1 file changed, 1 deletion(-) > > > > This makes sense to me and I could not find any possible typo alias > anywhere (like we have in virsh, for example). The only thing I am > unsure about is whether we want to actually use the proper naming. The > reason is that by default this is set to vla-larger-than=PTRDIFF_MAX > which is pretty huge number. On the other hand the man page for GCC > says it is only effective with -ftree-vrp (-02 and above). The -Wvla-larger-than=PTRDIFF_MAX default is irrelevant though, because we've blocked all use of VLAs by using -Wvla. IOW, AFAICT, -Wvla-larger-than and -Wvla are mutually exclusive from a conceptual POV.

> > I do not see whether using the predefined alloc_max would make sense or > not. So I am not against just removing it, but feel free to overrule me > as I did not look into this as much as others will be capable of. > > Reviewed-by: Martin Kletzander <mkletzan(a)redhat.com&gt; > > > diff --git a/meson.build b/meson.build > > index 4f23f9104e..40c841e777 100644 > > --- a/meson.build > > +++ b/meson.build > > @@ -390,7 +390,6 @@ cc_flags += [ > > '-Wvariadic-macros', > > '-Wvector-operation-performance', > > '-Wvla', > > - '-Wvla-larger-then=4031', > > '-Wvolatile-register-var', > > '-Wwrite-strings', > > ] > > -- > > 2.27.0 > > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|