[Bug c/71255] Implement #pragma may_alias

[manu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71255

Manuel López-Ibáñez <manu at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |manu at gcc dot gnu.org

--- Comment #23 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Florian Weimer from comment #22)
> (In reply to Marek Polacek from comment #21)
> > The testcase in Comment 14 should now compile fine.
> 
> What's the best way to detect that a compiler has this fix?  We cannot use a
> configure check.  Is there anything better than looking at __GNUC__?  Are
> you going to backport this fix?  Thanks.

It seems a good motivation to add the __has_feature(pragma_may_alias) PR6051.