Update: My LLVM-3.8+Clang-5 experiment revealed this sometimes also affects amd64: https://buildd.debian.org/status/fetch.php?pkg=irony-mode&arch=amd64&ver=1.2.0-2~exp1&stamp=1510272887&raw=0
Never on my amd64 development box, and only on the buildd. Also, good news! Upstream has committed a fix that I believe will probably do the trick. Cheers, Nicholas
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