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Slow compile times with Composer XE SP1

Daniel_F_6
Beginner
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I recently upgraded from Composer XE Update 1 to SP1 on a 64-bit Ubuntu 11.04 box. Prior to the upgrade, my build process took <1 minute. Now it hangs up on one file in particular and takes >7 minutes to complete. This file is kind of large ~1500 lines, includes several other files, and makes use of templates. I haven't changed anything about my build process. The only compiler flags I use are -O3 and -openmp. Any thoughts out there on this problem? Perhaps I'm using a 'feature' that is turned on by default now that wasn't previously?
Thanks.
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IDZ_A_Intel
Employee
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Daniel,
There are no fundamental changes from Update 1 to SP1. So we would need a reproducer or the full project if possible.If you can share something we should follow uponIntel Premier Support. Pls. advise.
Regards,
Hubert.
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Daniel_F_6
Beginner
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Thanks. I'll see what I can come up with for a reproducer (full project can't be sent). I should also add that removing '-O3' makes the compile time very reasonable (a few seconds)...of course this is expected.
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TimP
Honored Contributor III
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You might be able to find the location in your source code of a more aggressive optimization effort in the later compiler by comparing the opt-report-file output (preferably between the compiler versions, both with the same options, but possibly also between -O2 and -O3 with ther later compiler).
I've found in a few cases that the later compilers favor a switch to CEAN array notation in order to target the optimizations performed. I agree with the advice to submit a reproducer to see if the newer compiler is mis-targeting its efforts.
It's also possible that a more aggressive optimization has run into a shortage of RAM on your installation. In that case, cutting it down might make your problem go away.
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