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Re: [PATCH] Fix PR32628, bogus overflow flag on sizetype consts


On Tue, 15 Jan 2008, Richard Kenner wrote:

> > So, if you need error-checking you presumably know the signedness of
> > the computation you are doing.  What is required is that you do this
> > computation and error-checking _not_ in a TYPE_IS_SIZETYPE type.
> > You can then convert the (non-overflowed) result to a sizetype
> > only _after_ error checking.
> 
> Yes, but that involves nested NOP_EXPRs which are likely to be removed.

!?

We are talking about constants.  If you don't have constants, you
don't get "error checking" via TREE_OVERFLOW anyway.

Richard.


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