Brian Braatz wrote:
http://www.coyotegulch.com/reviews/gcc4/index.html
The review is interesting, but of most relevant interest to boosters would be the following:
"The C++ compiler is now faster, particularly on code heavy with templates; the Standard C++ library has improved stream and strings classes, and it includes preliminary new classes from the recent C++ Technical Report 1 (an update to Standard C++)."
The review is interesting. For those who don't wish to read through it, basically 4.0 is more of an incremental version, no real performance leaps in compilation or performance.
The time to compile KDE is reported to decrease by half, in debug settings: http://www.kdedevelopers.org/node/view/1004 which I find rather nice. On the downside, there's some bug that makes the resulting binaries broken, but probably that will be fixed relatively soon. - Volodya