Re: About processor optimisation with gcc

[Sreeji K Das <bksys@xxxxxxxx>]

Hi

man gcc says:
	"These  `-m' options are defined for the Intel 80386 family of
computers:"

Thus -m486 indicates Intel 486 or above. In the Kernel (as of
2.2.16) makefile, I see the following entry:

ifdef CONFIG_M586
CFLAGS := $(CFLAGS) -m486 -malign-loops=2 -malign-jumps=2 
-malign-functions=2 -DCPU=586
endif

ifdef CONFIG_M686
CFLAGS := $(CFLAGS) -m486 -malign-loops=2 -malign-jumps=2
-malign-functions=2 -DCPU=686
endif

So there's nothing like -m586 or -m686 (may be the latest gcc has that). 
I dunno about options specific to AMD.

Sreeji

On Tue, 14 Nov 2000, Shridhar Daithankar wrote:

> Hi all
> 
> I am just compiling a math library, ccmath. I would like to know how can
> 
> I compile for a specific processor. cc/gcc does not recognise anything
> beyond 486 and I am running a PIII(just confirmed...)
> 
> I wonder how kernel gets compiled for specific processor though. I lists
> 
> PII/PII/AMD/586/686 etc....
> 
> Any suggestions?
> 
> Bye
>   Shridhar
> 
> 
> 
> 
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