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Re: where can I get gcc optimizations information
- From: John Love-Jensen <eljay at adobe dot com>
- To: Juan Castillo <castillo at teisa dot unican dot es>
- Cc: MSX to GCC <gcc-help at gcc dot gnu dot org>
- Date: Mon, 12 Mar 2007 06:55:37 -0600
- Subject: Re: where can I get gcc optimizations information
Hi Juan,
> When using "-fverbose-asm" flag in the commmand line to produce the list of
> optimization passes, I suppose you mean adding the "-S" flag to see the
> assemble file, don't you? I say this because using the flag in a common
> compilation doesn't produce any change.
> Anyway, taking a look at the assemble file, I can see the flags employed when
> I compile with -O1 option, but if I introduce them all in the command line
> instead of -O1 (it is supposed that the executable file would be the same),
> optimizations are not performed. What am I doing wrong? I have read source
> code and -O1 flag activates some other flags and it seems it does not any
> more.
-O0 (which is the default if not specified) disables optimizations.
So introducing specific flagged optimizations in the context of
optimizations disabled has no effect.
HTH,
--Eljay