Debugging GCC Compile Times

Question

I'm creating a fairly large library in C++(0X) using gcc4.6 in linux. My library relies heavily on template classes, resulting in long compile times for applications which use the library. I would like to start speeding things up by providing explicit instantiations of the worst offending types/methods.

Is there a way to have gcc report the time spent compiling various types/methods so that I can apply my explicit instantiations in a principled way, rather than through intuition?

score 27 · Accepted Answer · answered Jun 17 '11 at 19:04

27

g++ some_file.cc -ftime-report

will give you a rough estimate of time spent in different compiler phase. Most important ones in your case are name lookup and parsing.

No way to get a per class/function compile time alas.

STeven Watanabe has proposed a template profiler , available in boost sandbox that helps getting the number of potential instantiation of anything in a .cc

answered Jun 17 '11 at 19:04

Joel Falcou

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said profiler link : https://svn.boost.org/svn/boost/sandbox/tools/profile_templates/ – Joel Falcou Jun 17 '11 at 19:58
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This would be more useful if there were any semblance of docs on how to use it. – xaxxon Jul 11 '16 at 09:31
@xaxxon There's a 'doc' folder :) – Bulletmagnet Sep 11 '17 at 11:45
I'm having a hard time figuring out how to use it based on just the docs folder. Steven's original post has a little more context: http://boost.2283326.n4.nabble.com/Profiling-template-instantiations-td2657157.html – Fractaly Dec 05 '19 at 22:50

score 1 · Answer 2 · answered Jun 17 '11 at 19:27

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I know that it's not what you're looking for, but maybe ccache/distcc may help to speed up compilation.

Also if you have multi core machine you may exploit make -jN to tell make run N jobs at once.

Don't forget about precompiled headers too.

answered Jun 17 '11 at 19:27

dimba

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Fortunately, I have server farm on which I compile - However, I'm trying to make things faster for any poor user that wants to compile all of these crazy templates. – rcv Jun 17 '11 at 22:31

Debugging GCC Compile Times

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