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Re: m68k bootstrapping broken

Andreas Schwab wrote: 
I sometimes get bootstrap failures on ia64, and the one and only
difference between stage2 and stage3 is two insns being swapped in a
single object file without any semantic change.  Those failures go away
when changing the environment in any way, and because of that I was unable
to debug that yet.

There is a known problem with the scheduler's use of cselib. This only happens on IA-64, because only IA-64 uses the sched-ebb.c file which enables use of cselib.

The problem is that the scheduler calls cselib, stores data returned from cselib in scheduler data structures, cselib frees the data when it doesn't need it anymore, and then the scheduler dereferences the already-freed data getting garbage.

There was a long discussion about this a few months ago, but it didn't come to any resolution. It was either Jakub or Jan that tracked down the problem to the scheduler's use of cselib. I think it was HJ that reported the initial bootstrapping bug.

I've never seen this problem on my machine.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com


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