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Re: [PATCH] Fix ACATS failures in GCC 3.4


> No, I think Roger's fix is sufficient and the real problem. The point
> of the code you're patching in fold is to find the simplest representation
> of the arguments so their form can be studied.  It's a serious error in
> fold to place those in the tree without converting them first.  The code
> he's patching makes that error.

OK, I see the disagreement here.  I thought it was always safe to strip casts 
that are deemed NOPs for a particular node.

> But as long as you're not losing information by stripping any
> sign-changing NOPs from the operand, it's safe to do so.  The only case
> where information is lost is the comparison case (since the type of the
> comparison node means something else), not MIN, MAX, or right shift.

Here I don't see it anymore.  Hence the question: is it safe or not safe to 
strip these NOPs for MAX_EXPR, since you're saying that only the type of the 
MAX_EXPR is supposed to matter?

-- 
Eric Botcazou


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