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    [GOLD] Fix powerpc64 optimization of TOC accesses
    
    Fixes a thinko.  Given code that puts variables into the TOC (a bad
    idea, but some see the TOC as a small data section) this bug could
    result in an attempt to optimize a sequence that should not be
    optimized.
    
    	* powerpc.cc (Target_powerpc::Scan::local): Correct dst_off
    	calculation for TOC16 relocs.
    	(Target_powerpc::Scan::global): Likewise.
    
    2017-11-08  Kyle Butt  <iteratee@google.com>
    
            * object.cc (do_find_special_sections): Fix a thinko with memmem return
            values and check for != NULL rather than == 0.