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

[Martin Kletzander]

On Thu, May 27, 2021 at 12:00:59PM +0100, Daniel P. Berrangé wrote:
>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 at redhat.com>
>> > ---
>> > 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.
>

Thank I misunderstood and this patch makes complete sense, sorry for the
noise and thanks for the correction.

>>
>> 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 at redhat.com>
>>
>> > 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
>-- 
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