Created attachment 28512 gdb backtrace Root cause:
PRE bases on the result of value numbering (run_scc_vn). At the end, it free_scc_vn. But before free_scc_vn, it might call cleanup_tree_cfg (); if (do_eh_cleanup || do_ab_cleanup) cleanup_tree_cfg (); cleanup_tree_cfg might call make_ssa_name which might reuse some "name" from the FREE_SSANAMES list. If the VN_INFO of the "name" is NULL, free_scc_vn will "Segmentation fault". Richard's patch makes "do_eh_cleanup" to false. So cleanup_tree_cfg is not called in PRE. Then no new ssa name will be created. bt.log shows the gdb backtrace to create a new ssa name. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1065559 Title: [regression] cone ftbfs on armel/armhf using GCC 4.7 To manage notifications about this bug go to: https://bugs.launchpad.net/gcc/+bug/1065559/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs