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Re: Patch: scheduling vs variable arrays


On Thu, Aug 08, 2002 at 06:12:35PM -0700, Geoff Keating wrote:
> It's OK to use RTX_UNCHANGING_P with stack variables that aren't
> popped, because those really won't change.  Well, sort of.

No it's not.

   {
     const int a = 4;
     &a;
   }
   {
     const int b = 5;
     &b;
   }

IIRC the stack slot may be re-used.  Even if it isn't, this is
a can of worms that should have been killed a long time ago.
We have something that _sort of_ works at the moment.  Change
any one thing and all bets are off.

Also IIRC, you will need to play with Ada to produce the worst
examples in this area.


r~


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