http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53455
--- Comment #11 from Niall Douglas <s_gccbugzilla at nedprod dot com> 2012-06-14 11:49:01 UTC --- (In reply to comment #9) > maybe related: https://svn.boost.org/trac/boost/ticket/6919 > Had similar crash issue. Though in my case (which may well be different from > the OP) rebuilding boost with new flags fixed it. > If OP posts crashtest.cpp source, I'll be happy to run it through. > Here's how I rebuilt the f17 rpms: > > # cat ~/.rpmrc > optflags: x86_64 -O2 -g -std=c++11 -fno-strict-aliasing > # rpmbuild --rebuild boost-1.48.0-11.fc17.src.rpm With respect to the Boost bugtracker, if this is an aliasing bug then it's a bug in Boost. Strict aliasing isn't an optional part of the ISO standard. They shouldn't have closed that issue because -fno-strict-aliasing "fixes" the bug on 4.7. Equally, it could still be that GCC 4.7 is performing an unsafe strict aliasing optimisation which it didn't do in 4.6. Weirdly the Boost bugtracker thinks the bug fixed in GCC 4.7, whereas this bug is about a 4.7 regression from 4.6. Niall