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Re: Handling non-constant bounds in extract_range_from_cond
- From: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
- To: law at redhat dot com
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Mon, 29 Nov 04 22:07:21 EST
- Subject: Re: Handling non-constant bounds in extract_range_from_cond
As you say, it may not be appropriate for Ada, but it is appropriate
for C and possibly other languages.
As far as I know, C doesn't use subtypes for objects. They are only
used in C except as representations of array bounds, so this never
comes up. What other languages use them?
It seems to me that the semantics of this stuff really needs to be for
the object to be converted into the base type, then compared to the
range of the subtype -- before we get to the gimplification phase.
As I said, the problem with that is that these conversions tend to be
stripped off by the optimizers. I suppose we could view those removals
as bugs ...