branches: 1.1.1.1.46; 1.1.1.1.58;
import GCC 4.1 branch from 20061021.

includes fixes for these 109 GCC PR's:

4520 13685 13983 17519 19505 20256 22209 22313 23454 24367 25211
25468 25519 25636 25636 26435 26504 26570 26719 26764 26881 26969
26983 26991 26991 26993 27075 27184 27226 27287 27287 27291 27334
27363 27428 27489 27490 27537 27558 27565 27566 27616 27639 27681
27697 27721 27724 27768 27793 27793 27795 27827 27878 27889 27893
28029 28075 28136 28148 28150 28162 28170 28187 28207 28207 28218
28221 28238 28243 28247 28257 28259 28267 28283 28286 28299 28386
28402 28403 28418 28473 28490 28493 28621 28634 28636 28649 28651
28677 28683 28726 28814 28825 28862 28900 28924 28946 28952 28960
28980 29006 29091 29119 29132 29154 29198 29230 29290 29323