lkml.org 
[lkml]   [2006]   [Jun]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] klibc
From
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    [W:0.077 / U:0.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site