Will check later today.
Extract from man gcc:
-mcpu=cpu-type
Tune to cpu-type everything applicable about the generated code,
except for the ABI and the set of available instructions. The
choices for cpu-type are i386, i486, i586, i686, pentium,
pentium-
mmx, pentiumpro, pentium2, pentium3, pentium4, k6, k6-2, k6-3,
athlon, athlon-tbird, athlon-4, athlon-xp and athlon-mp.
While picking a specific cpu-type will schedule things appropri-
ately 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. i586 is equivalent to pentium and i686 is
equivalent to pentiumpro. k6 and athlon are the AMD chips as
opposed to the Intel ones.
cheers
andrew
----- Original Message -----
From: "Mark Cave-Ayland" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Cc: "'Joe Conway'" <[EMAIL PROTECTED]>; "'Andrew Dunstan'"
<[EMAIL PROTECTED]>; "'Lamar Owen'" <[EMAIL PROTECTED]>; "'Postgresql
Hackers'" <[EMAIL PROTECTED]>
Sent: Tuesday, August 05, 2003 6:28 AM
Subject: Re: [HACKERS] problem with RH7.3 Pg7.3.4 binaries
> Hi Magnus,
>
> Thanks for that. I always believed that the mcpu flag could enable a C
> compiler to generate code that could use the extra instructions on the
> newer CPUs - perhaps one day I'll get around to reading the
> documentation ;)
>
> Anyway, I've posted the compiled RH 7.3 postgresql-7.3.4 RPMs at
> http://www.webbased.co.uk/mca/pgsql/. Andrew, if you are satisfied that
> these work correctly on your RH7.3 install, there is no problem with
> Lamar placing copies of them on the postgresql website for people to
> download.
>
>
> Cheers,
>
> Mark.
>
> ---
>
> Mark Cave-Ayland
> Webbased Ltd.
> Tamar Science Park
> Derriford
> Plymouth
> PL6 8BX
> England
>
> Tel: +44 (0)1752 764445
> Fax: +44 (0)1752 764446
>
>
> This email and any attachments are confidential to the intended
> recipient and may also be privileged. If you are not the intended
> recipient please delete it from your system and notify the sender. You
> should not copy it or use it for any purpose nor disclose or distribute
> its contents to any other person.
>
> > -----Original Message-----
> > From: Magnus Naeslund(w) [mailto:[EMAIL PROTECTED]
> > Sent: 05 August 2003 10:59
> > To: Mark Cave-Ayland
> > Cc: 'Joe Conway'; 'Andrew Dunstan'; 'Lamar Owen'; 'Postgresql Hackers'
> > Subject: Re: [HACKERS] problem with RH7.3 Pg7.3.4 binaries
> >
> >
> >
> > Mark Cave-Ayland said:
> > > Hi there,
> > >
> > > I have a RedHat 7.3 machine that can build the 7.3.4 RPMs
> > if required
> > > - it only contains RPMs from the vanilla CD or from
> > > updates.redhat.com. I've just done a test build and
> > everything seems
> > > OK except that the C compiler is passed the -mcpu=i686 flag - I'm
> > > guessing I need to somehow change this to i386 so it will binaries
> > > will run on actual i386 machines? Can someone point me in the right
> > > direction?
> > >
> >
> > The -mcpu flag doesn't do what you seems to think it does.
> > It still generates i386 compatible code, but favours i686
> > processor timings etc.
> >
> > >
> > > Cheers,
> > >
> > > Mark.
> >
> >
> > Magnus
> >
>
>
>
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