switch to __sync_bool_compare_and_swap for x86 instead of inline assembler
switch to __sync_bool_compare_and_swap for x86 instead of inline assembler

marioskogias/libfiber,marioskogias/libfiber,brianwatling/libfiber,marioskogias/libfiber,marioskogias/libfiber,brianwatling/libfiber,brianwatling/libfiber,brianwatling/libfiber