https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68771
--- Comment #11 from Daniel Vollmer <zerolo at gmail dot com> --- (In reply to Iain Sandoe from comment #9) > (In reply to Daniel Vollmer from comment #8) > > Using g++-7.4.0 I'm now seeing the following: > > - Step 1) (the compilation with "-flto -fprofile-generate") still works, > > So - to be sure - this is LTO without "-g"? > (we should expect LTO to work in general, without the debug scenario) Yes, all this is without "-g".