Comment # 3 on bug 1040105 from Martin Li��ka

Created attachment 725999 [details]
-fsanitize=ubsan report

I've tried to build the binary with -fsanitize=ubsan and I'm attaching report.
You can find it in my branch project:
https://build.opensuse.org/package/show/home:marxin:branches:openSUSE:Factory:Staging:C:DVD/MozillaFirefox-ubsan

To be honest, switching from -O3 to -O2 is for me just a work-around. The
source code contains many of such errors, which should be eventually fixed.
Running -fsanitize=address would be also interesting.