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Re: GCC 3.0 Status Report
Geoff Keating <geoffk@geoffk.org> writes:
> Mark Mitchell <mark@codesourcery.com> writes:
>
> > In the short term, we will focus on compile-time performance,
> > especially in C++. At that point, application testing will
> > become the major focus. Performance of the generated code
> > will be a greater focus of the 3.1 release.
>
> Hi Mark,
>
> I have some news for you, which might be good or might be bad, your
> choice :-).
>
> Jason Merrill took over the PCH stuff from where I left it, and
> finished the C++ support. Based on the numbers I had for C, I
> expected a 2x or 3x speed improvement, which is nice but not
> earth-shattering. However, we have some new numbers from Daniel
> Berlin which indicates that the speed improvement is more on the order
> of 20x, when compiling KDE; I guess I just didn't realize how huge C++
> headers were.
Just to give you some idea of the largeness of C++ headers, I took a
random KDE app, khotkeys, took all of the headers it includes that
aren't specific to itself (IE those in qt2/include and kde2/include
only), through them in a file, and -save-temps'd it, and removed
blank lines, to see how much code it was:
bash-2.04# cat test.cc
#include "test.h"
bash-2.04# cat test.h
#include <kapp.h>
#include <klineedit.h>
#include <kwin.h>
#include <krun.h>
#include <kdesktopfile.h>
#include <ksimpleconfig.h>
#include <kurifilter.h>
#include <kstddirs.h>
#include <kdebug.h>
#include <kuniqueapp.h>
#include <qtimer.h>
#include <dcopobject.h>
#include <kurifilter.h>
#include <kglobalaccel.h>
bash-2.04# remblanklines test.ii
bash-2.04# wc test.ii
8780 38085 300160 noblanks
This isn't uncommon, and is the very low end (khotkeys is three C++
files, total).
--Dan