[Bug fortran/49103] [4.6/4.7 Regression] local variables exchange values / wrong code with -O3

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49103

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-05-31 13:28:17 UTC ---
Created attachment 24402
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24402
gcc46-pr49103.patch

While micha's patch is the way to go for the trunk, it most likely isn't
backportable.
This untested hack is an attempt to avoid reverting my patch if the vars aren't
stored in bbs with significant code motion.  If anyone has better place to
set the bit, I'd appreciate it.