------- Comment #3 from zadeck at naturalbridge dot com 2009-01-10 01:57 ------- Created an attachment (id=17068) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17068&action=view) patch to cause df to verify after every patch
this is a combine bug. The df verification fails after combine makes some modification to the cc arg of insn 28 in the foo function that bypasses the implicit and explicit calls to mark the insn as being changed. I am looking into trying to figure out what path thru combine is doing this. However, if some combine expert (or just someone who wants to prove that they have better skill with the debugger than I do) wants to get there first, be my guest. I have attached a patch that improves some of the debugging and causes df to verify after every pass. This patch causes the failure to move from being in ira, to the start of if conversion after combine. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38774
