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Re: [patch] fix wrong gimple code with ptr to forward vla


Joseph S. Myers wrote:
On Fri, 1 Sep 2006, Mark Mitchell wrote:

I think that this is a more fundamental problem.  Since we only have one node
for a type, the first use of a pointer type may point to a variable-length
array whose size isn't known at the point the pointer type is used.

On that basis, I thin Jakub's patch is suspect for PR 21536, and that we
should not recur on pointer types.  Perhaps the middle-end should just ignore
the bounds for VLAs, and treat them as unknown, at least in some situations.

I think front ends should be responsible for making sure that VLA sizes get evaluated at the right time and replacing them with temporary variables, rather than relying on SAVE_EXPRs getting evaluated at a sensible time.

I think you've nailed it; that's exactly what we should do.


--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713


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