KDE sources now blacklist gcc 4.0.0 because it miscompiles KDE but that shouldn't be
a reason to do no compilation benchmarks, or? :-) My test machine was an Athlon XP
2600+ with 512MB and SUSE 9.3's gcc 3.3.5. The other gcc versions were pure gcc.
My first test was to compile Qt 3.3.4:
gcc 3.3.5 23m40 31m38
gcc 3.4.3 22m47 28m45
gcc 4.0.0 13m16 19m23
Next I compiled kdelibs/HEAD with --enable-final and unsermake -j 2: