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Re: gcc 4.3.0 i386 default question


> Hi,
> 
> Did the default i386 CPU model that gcc generates
> code for change between 4.2.x and 4.3.0?  I didn't
> see anything in the release notes that jumps out at
> me about this. 

There wasnt any intend to change the codebase.  However the default
tunning now has changed to "generic" model.  Perhaps some non-i386
instructions got in as a mistake.  Can you be more specific about what
instructions you found?

Honza
> 
> Using i386-rtems4.9 as the target, I was running
> code compiled by gcc 4.3.0 on a  vanilla i386 and
> was getting illegal instruction  exceptions.  I looked
> at the assembly and noticed instructions which were
> not on the i386.  Obviosuly, when I added -mtune=i386
> and the issue went away.
> 
> This probably impacts no one on a GNU/Linux computer
> since very few of those are base i386's anymore.  Just
> venerable embedded systems. :)
> 
> 
> -- 
> Joel Sherrill, Ph.D.             Director of Research & Development
> joel.sherrill@OARcorp.com        On-Line Applications Research
> Ask me about RTEMS: a free RTOS  Huntsville AL 35805
>   Support Available             (256) 722-9985
> 


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