http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50693
seems to be the specific issue, and it says it was fixed in 4.6.1.
It appears that the Changelog was modified thusly:
https://github.com/mirrors/gcc/commit/63f5ad449bbe0a4d478ae9...
I guess you could just download the source and see if it's in there.
EDIT: It is not.
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50693
seems to be the specific issue, and it says it was fixed in 4.6.1.