loc_mentioned_in_p invokes undefined behavior

[Eric Botcazou]

> I don't see any risk whatsoever.  All 3 uses are evidently dealing 
> with rtx.  Do you know of something I don't?

I've already exposed my position.

> I wouldn't mind turning the predicate into a void*, if that would make you
> more comfortable about risk management, but just changing the XVECEXP test
> while leaving a known inconsistency behind seems like bad engineering
> practice to me.

It's your interpretation, I don't see any inconsistency.

-- 
Eric Botcazou