[Bug bootstrap/48327] [4.7 Regression] Bootstrap comparison failure with ada since r171622

[law at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48327

--- Comment #3 from Jeffrey A. Law <law at redhat dot com> 2011-03-29 15:59:11 UTC ---
It's a problem with updating the SSA graph in a relatively uncommon case. 
We're failing to update a PHI argument correctly.  I'm still thinking about how
best to address the problem.