https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86872
--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> --- line-map.c has linemap_assert (reason != LC_ENTER_MACRO); line_map_ordinary *map = linemap_check_ordinary (new_linemap (set, start_location)); map->reason = reason; We get here with reason != LC_ENTER_MACRO and create linemap with start_location >= LINE_MAP_MAX_LOCATION.