lkml.org 
[lkml]   [2006]   [Jun]   [4]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateSat, 03 Jun 2006 23:30:34 -0700 (PDT)
SubjectRe: [PATCH] klibc
FromDavid Miller <>
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Sat, 03 Jun 2006 15:26:05 -0700

> __arch64__ is ugly; it doesn't say it's a sparc thing.  I have added 
> -D__sparc_v9__ to the sparc64 MCONFIG file, so I think that's fine.
> 
> Perhaps the right thing to do is to make this an archconfig.h configurable.

Please don't do this, I'll explain why.

Using __sparc_v9__ is incorrect, here is the lowdown on these defines:

1) __sparc_v9__ means "-mcpu={ultrasparc*,niagara}" or "-mcpu=v9".
   Although this is implied by "-m64" it can be used for 32-bit
   code too.
   __sparc_v9__ means "using v9 instructions" which does not
   necessarily mean 64-bit

2) "__sparc__ && __arch64__" means 64-bit sparc

People often get this wrong, and it certainly is confusing.

Jakub Jelinek gives a good explanation on the gcc mailing
list here:

	http://gcc.gnu.org/ml/gcc/2002-12/msg00108.html

Thanks.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-06-04 08:32    [from the cache]
©2003-2008