https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117696
Bug ID: 117696 Summary: LTO ignores -g3 debug info level Product: gcc Version: 14.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: rdiez-2006 at rd10 dot de Target Milestone: --- LTO seems to ignore the -g3 debug info level, which means macro definitions are not included in the debug information. I asked about it in the mailing list in February 2020, but got no answer: Debug info with C macros (-g3) not honoured in LTO builds https://gcc.gnu.org/legacy-ml/gcc-help/2020-02/msg00064.html Other people have noticed too: https://stackoverflow.com/questions/45340933/gcc-can-not-combine-flto-with-g-so-how-to-generate-debug-info If it does not work, then it should at least be documented in the GCC manual. It would also be nice if GCC could emit a warning when using -flto and -g3 together.