Re: pgcc optimizationss

Petko Manolov (petkan@varel.bg)
Wed, 16 Dec 1998 15:06:48 +0200


Alan Cox wrote:

> Well 2.1.x seems to be ok with egcs, and egcs current + the assembler
> patches Bernd and co have provided should be rock safe. Having said that
> you don't want to use -O6 with the kernel. -O6 says "please go around and
> inline things as you feel". The kernel authors have already done that and
> made a better job of it than the compiler will

True, but -O6 enables a lot of optimization that -O2 didn't. I prefer
-O6 -fno-inline-functions (i don't like wild inlining too). Sadly this
is broken in egcs/pgcc. I compiled stock 2.1.131 with pgcc-2.91.60
(egcs-1.1.1) and i'm using the kernel from a week without a crash
(-O6 used). But when tried with -fno-inline-functions the kernel
boots but when i try to login it oopses hard (scheduling in interrupt).
I think this is a compiler problem.
-O2 is quite stable since 1.0.1

regards

PS: Marc, is there some inline asm changes/fixes in pgcc/egcs-1.1.1.
compared with pgcc/egcs-1.1?

--
Petko Manolov - petkan@varel.bg
http://www.varel.bg/~petkan/

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