Just a bug report for fixing this: http://gcc.gnu.org/ml/gcc-patches/2004-11/msg01824.html
-- Summary: The stacks in tree-ssa-dom.c and tree-intossa (and other tree-*) should be VEC(tree_on_heap) Product: gcc Version: 4.0.0 Status: UNCONFIRMED Keywords: compile-time-hog Severity: minor Priority: P2 Component: tree-optimization AssignedTo: dnovillo at gcc dot gnu dot org ReportedBy: pinskia at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18618