public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
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 09:12:00 -0000	[thread overview]
Message-ID: <bug-60976-4-csaFTSoeWM@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 #17 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Rene Koecher from comment #14)
> I agree on your point here, however shouldn't an unchanged codebase (and
> we're not using C++11 features or -std=c++11 yet) at least keep the same
> performance?

No, because the standard library headers you include are not unchanged if you
upgrade the compiler.

> It's understandable that standards compliance can counter performance but I
> honestly wouldn't expect the compiler performance of older code / code not
> using the new features to drop that drastically..

Please provide a testcase demonstrating the problem with pre-C++11 code.


  parent reply	other threads:[~2015-04-09  9:12 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
2015-04-09  9:10 ` rene.koecher@wincor-nixdorf.com
2015-04-09  9:12 ` redi at gcc dot gnu.org [this message]
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

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=bug-60976-4-csaFTSoeWM@http.gcc.gnu.org/bugzilla/ \
    --to=gcc-bugzilla@gcc.gnu.org \
    --cc=gcc-bugs@gcc.gnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).