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Re: Optimization Switches
On Friday 27 August 2010 06:07 AM, Paul Brook wrote:
This is precisely what I want, segregating the effect of every single
I wish to selectively enable specific optimizations to observe its effect
on the source. My project requires me to do this analysis. It seemed, the
-f* flags would enable me to do that. But it turns out that individual
optimizations can't be enabled like that, and all the optimizations at a
specific level gets enabled when I use a -Ox switch. This faq at
http://gcc.gnu.org/wiki/FAQ#optimization-options, says this too.
So here are my two questions :
a) Is there any way to observe the effect of a particular optimization,
without the obvious option of using a lot of -fno switches.
b) And do the -f* switches serve any purpose, if I can't enable individual
optimizations using them.
I suspect that in practice that this isn't a particularly interesting
question. Optimizations often interact with each other in complex ways, with
the end result being significantly different to the naive sum of their parts.