When thunderbird and xulrunner (possibly also firefox itself, didn't check separately) are copiled with -march=native on my core-i7, they fail to launch (thunderbird) or crash frequently (firefox). Setting -march=core2 fixes the issue. As others seem to observe the same issue http://forums.gentoo.org/viewtopic-t-893300-start-0-postdays-0-postorder-asc-highlight-thunderbird.html , it might be worthwhile to add an ewarn message if -march=native is detected. NB: The problem was absent in previous versions of the packages. Reproducible: Always Steps to Reproduce: 1. Emerge packages with -march=native on a sandybridge system 2. Start thunderbird Actual Results: Nothing. Expected Results: Start up and show my mail folders. ;)
Please provide emerge --info.
Created attachment 285731 [details] emerge --info
Sorry, forgot it, there you go. For completeness sake (it's already in the description), here's gcc --version gcc (Gentoo 4.4.5 p1.3, pie-0.4.5) 4.4.5
Just for completeness: the problem is not the option "-march=native" by itself - the problem is, that "-march=native" results in the gcc option "-mavx" on Core i7 and some Sandy Bridge CPUs. https://bugs.gentoo.org/show_bug.cgi?id=352495 https://bugzilla.mozilla.org/show_bug.cgi?id=680547 As Christian suggested, it would be nice to have a warning if Thunderbird or xulrunner/Firefox are compiled with "-march=native". It would even be better if we could issue a warning or even an error if Thunderbird or xulrunner/Firefox are compiled with "-mavx" - but I have no idea if there is a way to detect a "-mavx" that results from "-march=native".
tb/fx-4 pass -mno-avx on gcc versions that support it >=4.4. bug is resolved.
