This is probably going to take some back and forth as I don't have any SPU target at hand to debug, so I have filed http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50801 to track this issue, along with a candidate fix. Could you please test it and reply to the bug with your results?
Thank you for your time and I apologize for the inconvenience.
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Dodji
