This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: GCC-3.4.0/PCH - some numbers incl. a bug report


Hi,

On: Thu, 29 Apr 2004 15:12:06 +0200 (CEST),
    Karel Gardas <kgardas@objectsecurity.com> wrote:

> I guess your source tree is not optimized for PCH enabled build. General
> hint which I have found during MICO hacking to be optimized for PCH build
> is: less PCH files you produce during the build, better. So you normaly
> end with one header file accumulating all needed header files and this is
> used for PCH enabled build. Then you are able to get much better numbers
> than you provided above.

Indeed. I took some time and did some more investigation and
timing. Just using -include bits/stdc++.h gives the biggest speedup.

g++-3.2.3
user    1m57.480s
sys     0m8.120s

g++-3.4.0
user    1m37.910s
sys     0m10.040s

g++-3.4.0-pc-stl
user    0m49.900s
sys     0m9.220s

Not bad. I leave the dumping of all headers into a single file and
precompiling this, as a task for another rainy afternoon.

Sincerely yours,
  René Rebe
    - ROCK Linux stable release maintainer

--  
René Rebe - Europe/Germany/Berlin
  rene@rocklinux.org rene@rocklinux-consulting.de
http://www.rocklinux.org http://www.rocklinux-consulting.de


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]