I can reproduce this bug as well on my feisty laptop (with all updates). Compiling with -O1 works:
[EMAIL PROTECTED]:/tmp$ time g++ -O1 -c -o quickbook.o quickbook.cpp real 0m29.831s user 0m28.926s sys 0m0.476s Compiling with -O2 does not seem to end (I waited 15 minutes which I assume is more than enough) [EMAIL PROTECTED]:/tmp$ time g++ -O2 -c -o quickbook.o quickbook.cpp (endless loop, or takes a very long time) According to g++ man page: -O2 turns on all optimization flags specified by -O. It also turns on the following optimization flags: -fthread-jumps -fcrossjumping -foptimize-sibling-calls -fcse-follow-jumps -fcse-skip-blocks -fgcse -fgcse-lm -fexpensive-optimizations -fstrength-reduce -fre‐ run-cse-after-loop -frerun-loop-opt -fcaller-saves -fpeephole2 -fschedule-insns -fschedule-insns2 -fsched-interblock -fsched-spec -fregmove -fstrict-aliasing -fdelete-null-pointer-checks -freorder-blocks -freorder-functions -falign-functions -falign-jumps -falign-loops -falign-labels -ftree-vrp -ftree-pre So I tried adding on top of -O1, all optimisation turned on by O2, in order to find the one which causes the bug. However, adding them all on top of -O1 does not trigger the bug: [EMAIL PROTECTED]:/tmp$ time g++ -O1 -fthread-jumps -fcrossjumping -foptimize-sibling-calls -fcse-follow-jumps -fcse-skip-blocks -fgcse -fgcse-lm -fexpensive-optimizations -fstrength-reduce -frerun-cse-after- loop -frerun-loop-opt -fcaller-saves -fpeephole2 -fschedule-insns -fschedule-insns2 -fsched-interblock -fsched-spec -fregmove -fstrict- aliasing -fdelete-null-pointer-checks -freorder-blocks -freorder- functions -falign-functions -falign-jumps -falign-loops -falign-labels -ftree-vrp -ftree-pre -c -o quickbook.o quickbook.cpp real 0m39.420s user 0m38.382s sys 0m0.560s Does it mean -O2 turns on optimisations that are not documented in g++ man page? -- g++: infinite loop with -O3 while compiling Boost.Quickbook from Boost CVS https://bugs.launchpad.net/bugs/82404 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs