We should renable the this flag at least at -O3 and above. See PR 15023 for why it was disabled, every
problem except for the compiler time issue was a latent target bug.
There are patches missing from 4.0 to fix some cases where regrename
could produce wrong code. Besides, enabling passes on a release branch
sounds like an awfully bad idea. Setting 4.1 as the target milestone
is more reasonable than 4.0.2 IMVHO.
I concur, done.
This has been fixed for -funroll-loops so closing as fixed as it is fixed as much as I filed it for.