------- Comment #11 from lthode at mail dot unomaha dot edu 2008-09-15 01:03 ------- (In reply to comment #9) > Thanks for the explanation, for the branch I would recommend an extra DCE > pass right before pass_del_ssa. On the trunk we need to make sure to run > this at -O0 as well. Note that the simple DCE can leave dead statements > around, only control-dependent DCE will make sure to not retain any > DCE opportunities. >
Well, I tried just that (running CD-DCE right before Out-of-SSA independent of optimization level) on the trunk, and 16 Fortran testcases blow up (with an ICE in Out-of-SSA) at -O0 due to it. However, turning optimization on makes them compile again, so running DCE at -O0 isn't such a great idea. On the other hand, this should be easy enough to fix on the branch, as we can just run the pass if optimization is enabled. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37102
