Here are some 4.2.0 RC2 test results (all languages except Ada). First, i686-pc-linux-gnu on RHEL 3. NOTE: if this release is built with the shipped compiler (3.2.3 based), we get a bootstrap comparison failure; the same is true with the FSF 3.2.3. This report used 3.4.2 as the bootstrap compiler, as well as binutils 2.17.
http://gcc.gnu.org/ml/gcc-testresults/2007-05/msg00029.html Next, x86_64-unknown-linux-gnu on RHEL3. In this case, the vendor compiler works OK as the bootstrap compiler: http://gcc.gnu.org/ml/gcc-testresults/2007-05/msg00026.html