Hello, I wanted to report running into an apparent gcc 4.1.2 bug; see the test case at https://svnweb.cern.ch/trac/lcgdm/attachment/ticket/514/tx.c (compare optimised/ non-optimised result) This showed up on SL5 x86_64 (gcc 4.1.2). I haven't reported it to gcc as the the gcc 4.1 branch is closed and I can't reproduce the problem on a plain gcc from a current branch. I think it is most likely closely related to these old bugs: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32327 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39604 Our current proposal is to continue with SL5 builds with the optimiser on, but with "-fno-tree-sink" Yours, David -- ------------------------------------------------------------------------- David Smith e-mail: [log in to unmask] tel: +41 22 76 70394 Address: D. Smith, CERN G06600, Bat 28 R-003, 1211 Geneva 23, Switzerland -------------------------------------------------------------------------