Re: Compiling with high optimization?

2003-02-09 Thread Jacques A. Vidrine
On Sat, Feb 08, 2003 at 05:23:01PM -0800, Terry Lambert wrote: The compiler didn't complain when he checked it before committing it because optimization was off by default; it should have complained, e.g.: Is that really what you meant? I don't believe it has anything to do with

Re: Compiling with high optimization?

2003-02-09 Thread Adrian Chadd
On Sat, Feb 08, 2003, David Schultz wrote: Yes, the possibility of being bitten by compiler bugs is certainly higher with higher optimization levels. Alpha with -O2 seems to have been broken for years, and I have seen strange things happen on IA64 as well. But the i386 code generators have

Re: Compiling with high optimization?

2003-02-09 Thread Erik Trulsson
On Sun, Feb 09, 2003 at 08:03:57AM -0600, Jacques A. Vidrine wrote: On Sat, Feb 08, 2003 at 05:23:01PM -0800, Terry Lambert wrote: The compiler didn't complain when he checked it before committing it because optimization was off by default; it should have complained, e.g.:

Re: Compiling with high optimization?

2003-02-09 Thread Jacques A. Vidrine
On Sun, Feb 09, 2003 at 03:17:12PM +0100, Erik Trulsson wrote: On Sun, Feb 09, 2003 at 08:03:57AM -0600, Jacques A. Vidrine wrote: On Sat, Feb 08, 2003 at 05:23:01PM -0800, Terry Lambert wrote: The compiler didn't complain when he checked it before committing it because optimization

Re: Compiling with high optimization?

2003-02-09 Thread Terry Lambert
Jacques A. Vidrine wrote: On Sat, Feb 08, 2003 at 05:23:01PM -0800, Terry Lambert wrote: The compiler didn't complain when he checked it before committing it because optimization was off by default; it should have complained, e.g.: Is that really what you meant? I don't

Re: Compiling with high optimization?

2003-02-09 Thread David Schultz
Thus spake Adrian Chadd [EMAIL PROTECTED]: On Sat, Feb 08, 2003, David Schultz wrote: Yes, the possibility of being bitten by compiler bugs is certainly higher with higher optimization levels. Alpha with -O2 seems to have been broken for years, and I have seen strange things happen on

Re: Compiling with high optimization?

2003-02-09 Thread Marcin Dalecki
David Schultz wrote: Strangely, gcc in FreeBSD 5.0 actually generates *slower* code when compiling for more recent architectures than when compiling for a 386. I don't know whether that is a bug in gcc or whether gcc is using some fancy feature like SSE that the kernel handles poorly on context

Re: Compiling with high optimization?

2003-02-09 Thread David Schultz
Thus spake Marcin Dalecki [EMAIL PROTECTED]: David Schultz wrote: Strangely, gcc in FreeBSD 5.0 actually generates *slower* code when compiling for more recent architectures than when compiling for a 386. I don't know whether that is a bug in gcc or whether gcc is using some fancy feature

Re: Compiling with high optimization?

2003-02-09 Thread Bernd Walter
On Sat, Feb 08, 2003 at 04:25:42PM -0800, David Schultz wrote: Yes, the possibility of being bitten by compiler bugs is certainly higher with higher optimization levels. Alpha with -O2 seems to have been broken for years, and I have seen strange things happen on IA64 as well. But the i386

Re: Compiling with high optimization?

2003-02-09 Thread Marcin Dalecki
David Schultz wrote: Thus spake Marcin Dalecki [EMAIL PROTECTED]: David Schultz wrote: Strangely, gcc in FreeBSD 5.0 actually generates *slower* code when compiling for more recent architectures than when compiling for a 386. I don't know whether that is a bug in gcc or whether gcc is using

Re: Compiling with high optimization?

2003-02-09 Thread Terry Lambert
Marcin Dalecki wrote: David Schultz wrote: Strangely, gcc in FreeBSD 5.0 actually generates *slower* code when compiling for more recent architectures than when compiling for a 386. I don't know whether that is a bug in gcc or whether gcc is using some fancy feature like SSE that the

Re: Compiling with high optimization?

2003-02-09 Thread Doug Barton
On Sun, 9 Feb 2003, Bernd Walter wrote: I'm always compiling -current on alpha and i386 with -O2 since months. I havn't noticed any compiler related problems lately. How do you know? -- The last time France wanted more evidence, it rolled right through Paris with a German flag.

Re: Compiling with high optimization?

2003-02-09 Thread Bernd Walter
On Sun, Feb 09, 2003 at 08:58:36PM -0800, Doug Barton wrote: On Sun, 9 Feb 2003, Bernd Walter wrote: I'm always compiling -current on alpha and i386 with -O2 since months. I havn't noticed any compiler related problems lately. How do you know? It's not that I don't know about things

Compiling with high optimization?

2003-02-08 Thread Ray Kohler
Has anyone tried building world/kernel with high optimizations (-O2, -O3) recently? What breaks? (Booby prize to whoever says common sense ;) I last tried it quite a few months ago and the resolver died on me, don't know what else. I'm not really thinking of running like that, but I am curious

Re: Compiling with high optimization?

2003-02-08 Thread David Schultz
Thus spake Ray Kohler [EMAIL PROTECTED]: Has anyone tried building world/kernel with high optimizations (-O2, -O3) recently? What breaks? (Booby prize to whoever says common sense ;) I last tried it quite a few months ago and the resolver died on me, don't know what else. I'm not really

Re: Compiling with high optimization?

2003-02-08 Thread Terry Lambert
David Schultz wrote: Thus spake Ray Kohler [EMAIL PROTECTED]: Has anyone tried building world/kernel with high optimizations (-O2, -O3) recently? What breaks? (Booby prize to whoever says common sense ;) I last tried it quite a few months ago and the resolver died on me, don't know what

Re: Compiling with high optimization?

2003-02-08 Thread David Schultz
Thus spake Terry Lambert [EMAIL PROTECTED]: David Schultz wrote: Thus spake Ray Kohler [EMAIL PROTECTED]: Has anyone tried building world/kernel with high optimizations (-O2, -O3) recently? What breaks? (Booby prize to whoever says common sense ;) I last tried it quite a few months ago

Re: Compiling with high optimization?

2003-02-08 Thread Terry Lambert
David Schultz wrote: Thus spake Terry Lambert [EMAIL PROTECTED]: Actually, failure to use optimization suppresses some compilation warnings, particularly those which normally print from using some variables without initializing them. I think you're thinking of dataflow analysis, which I

Re: Compiling with high optimization?

2003-02-08 Thread David Schultz
Thus spake Terry Lambert [EMAIL PROTECTED]: David Schultz wrote: Thus spake Terry Lambert [EMAIL PROTECTED]: Actually, failure to use optimization suppresses some compilation warnings, particularly those which normally print from using some variables without initializing them. I

Re: Compiling with high optimization?

2003-02-08 Thread Conrad Sabatier
On 08-Feb-2003 Ray Kohler wrote: Has anyone tried building world/kernel with high optimizations (-O2, -O3) recently? What breaks? (Booby prize to whoever says common sense ;) I last tried it quite a few months ago and the resolver died on me, don't know what else. I'm not really thinking of

Re: Compiling with high optimization?

2003-02-08 Thread Conrad Sabatier
On 09-Feb-2003 Dan Nelson wrote: In the last episode (Feb 08), Conrad Sabatier said: Call me a fool, but I've been using this for quite some time now, in both -stable (well, with slight modifications) and -current: CPUTYPE?=k7 CFLAGS= -O2 -pipe -mmmx -m3dnow -fforce-mem -fforce-addr

Re: Compiling with high optimization?

2003-02-08 Thread Dan Nelson
In the last episode (Feb 08), Conrad Sabatier said: Call me a fool, but I've been using this for quite some time now, in both -stable (well, with slight modifications) and -current: CPUTYPE?=k7 CFLAGS= -O2 -pipe -mmmx -m3dnow -fforce-mem -fforce-addr -fstrength-reduce \ -fthread-jumps