https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64930
--- Comment #9 from Alan Modra <amodra at gmail dot com> --- My point was that if you write a testcase that specifically tests for consume and get acquire code then that is a fail. The code generated is using a bigger hammer than necessary. Imagine for a moment if gcc promoted everything to seq_cst. That would also be "supporting" the atomics, but for powerpc we'd be quite unhappy and would want to know about such a change with a testsuite failure.. I recognize that the testcase doesn't properly test consume semantics, and that teaching gcc to track dependencies is not simple. Huh, I just checked and it appears powerpc emits unnecessary isyncs for atomic_load consumes prior to the pr59448 change, probably in recognition that dependency tracking isn't done. So I withdraw my objection to adjusting the isync counts.