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Re: Bug in gcc CVS HEAD from a few days ago with alloca and stack alignment


Kevin B. Hendricks <khendricks@ivey.uwo.ca> writes:

> Hi David,
> 
> Thanks!  
> 
> I changed STACK_BOUNDARY to 128 and rebuilt the entire gcc and now everything 
> has started working including the gcj closure code and the gij interpreter.
> 
> Will you please commit a proper fix?  Franz's mail machine bounced my last 
> mail so I don't think he knows about this problem.

The proper fix is to find out what part of the compiler is failing to
honour ABI_STACK_BOUNDARY and fix that.  I don't think changing
STACK_BOUNDARY to 128 gives any significant benefits for optimisation as yet,
since there aren't yet any operations that need that alignment.

> > So it looks to me that this is some incorrect accomodation made >
> for eABI, i.e., someone trying to use the sysv4 configuration for
> eABI > instead of creating a real cross-compiler.

I believe it's to allow linking of sysv4 code with eabi code,
primarily to save on multilibs.  STACK_BOUNDARY is the stack alignment
that the compiler can assume, ABI_STACK_BOUNDARY is the stack
alignment that the compiler should preserve.

-- 
- Geoffrey Keating <geoffk@geoffk.org>


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