Re: [PATCH] detect attribute mismatches in alias declarations (PR 81824)

[Martin Sebor <msebor at gmail dot com>]

On 11/12/2018 11:29 AM, Matthew Malcomson wrote:
> Hello Martin,
>
> The new testcase Wattribute-alias.c fails on targets without ifunc
> support (e.g. aarch64-none-elf cross-build).
>
> It seems that just adding a directive `{ dg-require-ifunc "" }` to the
> test file changes the test to unsupported instead of having a fail.
>
> I don't know much about this patch so I don't know if the non-ifunc
> checks would still be useful on such targets.
>
> Would the simple change be OK? or would it be best to split the test
> file into multiple parts to still run the other checks?

I just committed the former change earlier today but splitting
the test would have probably been a better way to go.  Thanks
for reporting it just the same!  If you would prefer to split
the test that would be fine with me.

Martin

> Regards,
> Matthew
>
>
> On 09/11/18 17:33, Martin Sebor wrote:
> > > > +/* Handle the "copy" attribute by copying the set of attributes
> > > > +   from the symbol referenced by ARGS to the declaration of *NODE.  */
> > > > +
> > > > +static tree
> > > > +handle_copy_attribute (tree *node, tree name, tree args,
> > > > +               int flags, bool *no_add_attrs)
> > > > +{
> > > > +  /* Break cycles in circular references.  */
> > > > +  static hash_set<tree> attr_copy_visited;
> > > Does this really need to be static?
> >
> > The variable was intended to break cycles in recursive calls to
> > the function for self-referential applications of attribute copy
> > but since the attribute itself is not applied (anymore) such cycles
> > can no longer form.  I have removed the variable and simplified
> > the handlers (there are tests to verify this works correctly).
> >
> > > > diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
> > > > index cfe6a8e..8ffb0cd 100644
> > > > --- a/gcc/doc/extend.texi
> > > > +++ b/gcc/doc/extend.texi
> > > > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> > > > index 5c95f67..c027acd 100644
> > > > --- a/gcc/doc/invoke.texi
> > > > +++ b/gcc/doc/invoke.texi
> > > [ ... ]
> > >
> > > > +
> > > > +In C++, the warning is issued when an explicitcspecialization of a
> > > > primary
> > > "explicitcspecialization" ? :-)
> >
> > Fixed.
> >
> > > Looks pretty good.  There's the explicit specialization nit and the
> > > static vs auto question for attr_copy_visited.  Otherwise it's OK.
> >
> > Thanks.  I've retested a revision with the changes discussed here
> > and committed it as r265980.
> >
> > Martin