https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78685
--- Comment #35 from Lukas Grätz <lukas.gra...@tu-darmstadt.de> --- (In reply to Jakub Jelinek from comment #31) > That is nonsense. > -O0 -fvar-tracking doesn't work and would be substantial amount of work, far > more than artificially adding uses of all vars at the end of their scopes > for -Og. I do not understand what you mean, -O0 -fvar-tracking works without a warning indicating that something went wrong. That said, I am not entirely sure if you really need that option for -O0. According to your GCC documentation, it might be needed. If I remember correctly, DWARF should contain the debugging info also for the prolog/epilog but the base frame is computation is more difficult there. I agree with Konstantin Kharlamov about the misleading documentation, I also observed that -O0 often provides a better debugging experience.
