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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/60976] Compilation with G++ 4.9.0 is 2-3 times slower than with 4.8.2
Date: Thu, 09 Apr 2015 09:07:00 -0000	[thread overview]
Message-ID: <bug-60976-4-K6lFR0RtBy@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-60976-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60976

--- Comment #15 from Jonathan Wakely <redi at gcc dot gnu.org> ---
For the program in comment 5 most of the difference in compile-time is caused
by the allocator-aware container requirements (additional constructors which
need to be instantiated for every explicit instantiation in the program and
more complicated definitions for copy/move/swap). These changes are required
for C++11 conformance, and I don't see any obvious way to implement them
without affecting compile times.

There is also some increase in compile-time caused by extra 'noexcept'
specifications added to lots of functions, especially iterator member functions
and operators. Not all of those are required by the standard, but they are
important nonetheless.


  parent reply	other threads:[~2015-04-09  9:07 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-26 15:36 [Bug c++/60976] New: " astellar at ro dot ru
2014-04-26 15:37 ` [Bug c++/60976] " astellar at ro dot ru
2014-04-26 15:38 ` astellar at ro dot ru
2014-04-26 15:38 ` astellar at ro dot ru
2014-04-28 22:56 ` astellar at ro dot ru
2014-04-28 22:56 ` astellar at ro dot ru
2014-04-28 22:57 ` astellar at ro dot ru
2014-04-28 22:58 ` astellar at ro dot ru
2014-04-28 22:58 ` astellar at ro dot ru
2014-04-28 22:59 ` astellar at ro dot ru
2014-04-29  7:58 ` redi at gcc dot gnu.org
2015-04-08  7:00 ` rene.koecher@wincor-nixdorf.com
2015-04-08  8:42 ` trippels at gcc dot gnu.org
2015-04-08  9:02 ` redi at gcc dot gnu.org
2015-04-09  7:16 ` rene.koecher@wincor-nixdorf.com
2015-04-09  9:07 ` redi at gcc dot gnu.org [this message]
2015-04-09  9:10 ` rene.koecher@wincor-nixdorf.com
2015-04-09  9:12 ` redi at gcc dot gnu.org
2015-04-09  9:47 ` trippels at gcc dot gnu.org
2015-10-19 19:21 ` ott at fb dot com
2015-10-19 20:54 ` redi at gcc dot gnu.org
2015-10-19 21:25 ` redi at gcc dot gnu.org
2015-10-19 22:42 ` ott at fb dot com
2015-10-20  0:05 ` redi at gcc dot gnu.org
2015-10-21  3:32 ` ott at fb dot com
2015-10-21 19:33 ` ott at fb dot com
2015-10-21 20:27 ` redi at gcc dot gnu.org
2015-10-22  6:35 ` rene.koecher@wincor-nixdorf.com
2015-10-22  7:12 ` ott at fb dot com
2015-10-25  2:56 ` redi at gcc dot gnu.org

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