https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107950
--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> --- Oh, the function has 2 different definitions in C and C++ FE: gcc/c/c-objc-common.cc:range_label_for_type_mismatch::get_text (unsigned /*range_idx*/) const gcc/cp/error.cc:range_label_for_type_mismatch::get_text (unsigned /*range_idx*/) const And so that's why I see the linker error for 'lto' binary, interesting..