https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82229
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |lto, missed-optimization Status|UNCONFIRMED |WAITING Last reconfirmed| |2017-09-18 Ever confirmed|0 |1 --- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- I suspect changes in cross-module inlining causing the issue. Without some analysis from your side it's really hard to do anything about this. A good start is to do some profiling.