From:	"Nick Kurshev" <nickols_k AT mail DOT ru>
To:	"pgcc AT delorie DOT com" <pgcc AT delorie DOT com>
Date:	Tue, 23 Jan 2001 20:59:10 +0000 (:)
X-Mailer:	PMMail 2.00.1500 for OS/2 Warp 4.05
MIME-Version:	1.0
Subject:	Re: Re: pgcc-2.95.2.1 does not compile a Linux-kernel and has other bugs
Message-Id:	<E14L7pB-000EWS-00@smtp6.port.ru>
Reply-To:	pgcc AT delorie DOT com

Hello!

As continuation previous bugreport:

> Do not use experimental options. pgcc handles bash fine without -mmx.
>
>> And last observation: New compiler (pgcc-2.95.2.1)  is stopped too frequently ( by signals of different kind:
>> such as: 4, 9, 11). As rule, gcc received signal #11 or #9 only when memory is exhausted. But in this case 
>> free memory was ~50Mb. Also it does not remove wrongly generated .o file after receiving such signals. (but 
>> gcc does it).
>
>This indicates an overclocked machine or broken hardware (e.g. memory).
>pgcc reacts in exactly the same way to signals as gcc does. If you have
>any signals that you cannot reproduce this is a hardware problem. pgcc
>generates tighter code and it is well possible that you gcc-compiled
>programs run more-or-less reliably on overclocked chips/memoory but pgcc
>ones don't.

I have recompiled pgcc-2.95.2.1 with following options:
-march=k6 -mcpu=k6 -fschedule-insns2 -O9 -fomit-frame-pointer -pipe -ffast-math

And it works fine for a day. IMHO problem was not in hardware (Other operating systems never cause any 
problems). Problems are in -mmx and -mmx-only keys that are perfectly unstable ones.

Also I did an attempt to compile XFree-4.02 with following keys
 BOOTSTRAPCFLAGS="-march=k6 -mcpu=k6 -fschedule-insns2 -O9 -fomit-frame-pointer -mschedule-prologue 
-momit-leaf-frame-pointer -mmove -fmove-all-movables -freduce-all-givs -fexpensive-optimizations -fregmove 
-foptimize-register-move -fno-exceptions -fno-rtti -pipe -ffast-math"
CDEBUGFLAGS="-march=k6 -mcpu=k6 -fschedule-insns2 -O9 -fomit-frame-pointer -mschedule-prologue 
-momit-leaf-frame-pointer -mmove -fmove-all-movables -freduce-all-givs -fexpensive-optimizations -fregmove 
-foptimize-register-move -fno-exceptions -fno-rtti -pipe -ffast-math"
CXXDEBUGFLAGS="-march=k6 -mcpu=k6 -fschedule-insns2 -O9 -fomit-frame-pointer -mschedule-prologue 
-momit-leaf-frame-pointer -mmove -fmove-all-movables -freduce-all-givs -fexpensive-optimizations -fregmove 
-foptimize-register-move -fno-exceptions -fno-rtti -pipe -ffast-math"

Executables was perfectly not capable for work and did crash my Linux console (means: keyboard and mouse). 
Only button "reset" was ready.

When I changed -09 option with -O2 and recompile XFree again - all work fine.
As I see - pgcc uses unstable optimizations when optimization level is greate of 2.
May be it would be better to disable such optimizations and enable them only by user opinion?

Regards! Nick

P.S.: pgcc is cool compiler!

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