[PATCH] PR85678: Change default to -fno-common

[Richard Biener]

On Mon, Oct 28, 2019 at 10:39 PM Iain Sandoe <idsandoe@googlemail.com> wrote:
>
> Wilco Dijkstra <Wilco.Dijkstra@arm.com> wrote:
> >>>
> >>> I suppose targets can override this decision.
> >> I think they probably could via the override_options mechanism.
> >
> > Yes, it's trivial to add this to target_option_override():
> >
> >  if (!global_options_set.x_flag_no_common)
> >    flag_no_common = 0;
>
> for the record,  Darwin bootstraps OK with the change (which is to be expected,
> since the preferred setting for it is -fno-common).
>
> Testsuite fails are order “a few hundred” mostly seem to be related to tree-prof
> and vector tests (plus the anticipated scan-asm stuff, where code-gen will have
> changed).  I don’t have cycles to analyse the causes right now - but that gives
> an idea.

Note the vectorizer tests use explicit -fno-common ... (because we
can't re-align
globals if they are COMMON)

Richard.

> cheers
> Iain
>
>
>