Hi, I have successfully build GCC4.5 on my Fedora12. And I want to test the automatic parallelization feature of GCC4.5. I write a system program and compile it with flags: -O2 -fno-loop-strip-mine -floop-interchange -fgraphite-identity -ftree-parallelize-loops=4 -floop-parallelize-all -fdump-tree-graphite-all But I got the following error: block.c:1:0: sorry, unimplemented: Graphite loop optimizations cannot be used I am confused. It seems the error is related to the flag "-floop-parallelize-all". Does anyone knows what the problem is? Thanks. -- zhouxu