Andrzej Giniewicz wrote: >> That's interesting. tree-dce is Dead Code Elimination on trees, where >> gcc removes code that can't possibly be reached. It's possible that >> there's a bug in DCE, but I bet it's something like the enum bug above. >> If you're interested in finding the real bug I can tell you how to read >> the compiler dumps. > > that would be sweet, finding real bugs is always better than workaround :) Compile with -fdump-tree-all. You'll see dozens of dump files like hello.c.037t.addressables2 hello.c.036t.dce1 hello.c.035t.mergephi1 hello.c.034t.copyprop1 hello.c.033t.esra hello.c.032t.sdse1 hello.c.031t.addressables1 hello.c.030t.forwprop1 Diff the pass before dce and the post-dce dump and you'll see what dce did. There are several dce passes. Also, you can diff the final optimized code with and without dce. Andrew.
