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SubjectRe: gcc 2.8.0 seems OK here...
FromRobert Bihlmeyer <>
Date21 Mar 1998 10:47:22 +0100
Hi,

>>>>> On Fri, 20 Mar 1998 23:33:05 +0100 (CET)
>>>>> Marek Habersack <grendel@vip.maestro.com.pl> said:

 Marek> On Fri, 20 Mar 1998, Niels Kristian Bech Jensen wrote:

 >> The option -mpentium doesn't affect the instruction
 >> scheduling. Those with problems have used -march=pentium (have you
 >> tried that.)
 Marek> Exatctly. The -mpentium flag merely instructs gcc to output
 Marek> i586 opcodes, but the code isn't optimized any more than with
 Marek> the usual -m486 (save for the opcodes, of course)

Contrariwise. From the gcc manual:

`-mcpu=CPU TYPE'
     Assume the defaults for the machine type CPU TYPE when scheduling
     instructions.  The choices for CPU TYPE are: `i386', `i486',
     `i586' (`pentium'), `pentium', `i686' (`pentiumpro') and
     `pentiumpro'. While picking a specific CPU TYPE will schedule
     things appropriately for that particular chip, the compiler will
     not generate any code that does not run on the i386 without the
     `-march=CPU TYPE' option being used.

`-march=CPU TYPE'
     Generate instructions for the machine type CPU TYPE.  The choices
     for CPU TYPE are: `i386', `i486', `pentium', and `pentiumpro'.
     Specifying `-march=CPU TYPE' implies `-mcpu=CPU TYPE'.

`-m386'
`-m486'
`-mpentium'
`-mpentiumpro'
     Synonyms for -mcpu=i386, -mcpu=i486, -mcpu=pentium, and
     -mcpu=pentiumpro respectively.

-- 
Robert Bihlmeyer	reads: Deutsch, English, MIME, Latin-1, NO SPAM!
<robbe@orcus.priv.at>	<http://stud2.tuwien.ac.at/~e9426626/sig.html>

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