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* Optimization and Warning documentation
@ 2002-09-27  8:08 david.rasmussen
  0 siblings, 0 replies; 3+ messages in thread
From: david.rasmussen @ 2002-09-27  8:08 UTC (permalink / raw)
  To: gcc

Where can I read about exactly what each optimization and warning options
does,  and what optimizations -O[1,2,3] include and what warnings -w, -W and
-Wall etc. includes?

/David

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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Optimization and Warning documentation
  2002-09-27  8:29 ` David Rasmussen
@ 2002-09-27  8:44   ` Pop Sébastian
  0 siblings, 0 replies; 3+ messages in thread
From: Pop Sébastian @ 2002-09-27  8:44 UTC (permalink / raw)
  To: David Rasmussen; +Cc: gcc, luda_s

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On Fri, Sep 27, 2002 at 05:08:27PM +0200, David Rasmussen wrote:
> On Fri, 2002-09-27 at 14:56, ????????? wrote:
> > Deardavid.rasmussen£¡
> >    You can download the gcc manual from http://gcc.gnu.org.
> >    You can look up them in the  comand option section of the gcc  manual.
> > ¡¡¡¡
> 
> The problem is that many things are not stated explicitly. For example,
> does -w really enable _all_ warnings, every last one of them?
> And does any of the optimizations (O2, O3) include
> -foptimize-sibling-calls for example? It is not stated explicitly what
> options -O3 implies.
> 

Given that this is the development mailing list, I would say that you can 
have a look at gcc/toplev.c in GCC sources.

The variable optimize corresponds to the level of optimization you specify:
ie. if you compile with -O2 then optimize = 2.

Attached files are the call graph of the function rest_of_compilation 
(that corresponds to optimizations on RTL). Bracketed expressions correspond
to conditions.  This graph is not complete, thus you have to refer to the 
source code for more precise informations.


Sebastian

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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Optimization and Warning documentation
       [not found] <20020927125536.23083gmx1@mx018-rz3.gmx.net>
@ 2002-09-27  8:29 ` David Rasmussen
  2002-09-27  8:44   ` Pop Sébastian
  0 siblings, 1 reply; 3+ messages in thread
From: David Rasmussen @ 2002-09-27  8:29 UTC (permalink / raw)
  To: gcc; +Cc: luda_s

On Fri, 2002-09-27 at 14:56, 陆仲达 wrote:
> Deardavid.rasmussen£¡
>    You can download the gcc manual from http://gcc.gnu.org.
>    You can look up them in the  comand option section of the gcc  manual.
> ¡¡¡¡

The problem is that many things are not stated explicitly. For example,
does -w really enable _all_ warnings, every last one of them?
And does any of the optimizations (O2, O3) include
-foptimize-sibling-calls for example? It is not stated explicitly what
options -O3 implies.

/David

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2002-09-27 15:29 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2002-09-27  8:08 Optimization and Warning documentation david.rasmussen
     [not found] <20020927125536.23083gmx1@mx018-rz3.gmx.net>
2002-09-27  8:29 ` David Rasmussen
2002-09-27  8:44   ` Pop Sébastian

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