https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69985
--- Comment #14 from David Malcolm <dmalcolm at gcc dot gnu.org> --- (gdb) p *map $8 = {<line_map> = {start_location = 98229568, reason = LC_RENAME_VERBATIM}, to_file = 0x2709850 "cmds-check.c", to_line = 7836, included_from = -1, sysp = 0 '\000', m_column_and_range_bits = 12, m_range_bits = 5} (gdb) call linemap_lookup (set, r) $9 = (const line_map *) 0x7ffff15baf40 (gdb) p *(const line_map_ordinary *)$9 $11 = {<line_map> = {start_location = 98233888, reason = LC_RENAME}, to_file = 0x2709850 "cmds-check.c", to_line = 7837, included_from = -1, sysp = 0 '\000', m_column_and_range_bits = 13, m_range_bits = 5} The .i file has: if (!silent) fprintf( # 7836 "cmds-check.c" 3 4 stderr # 7836 "cmds-check.c" , "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) mismatch with block group[%llu, %u, %llu]: offset(%llu), objectid(%llu), flags(%llu)\n", The relevant code in cmds-check.c looks like this: 7835 if (!silent) 7836 fprintf(stderr, 7837 "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) mismatch with block group[%llu, %u, %llu]: offset(%llu), objectid(%llu), flags(%llu)\n", 7838 chunk_rec->objectid, 7839 chunk_rec->type, 7840 chunk_rec->offset, 7841 chunk_rec->length, 7842 chunk_rec->offset, 7843 chunk_rec->type_flags, 7844 block_group_rec->objectid, 7845 block_group_rec->type, 7846 block_group_rec->offset, 7847 block_group_rec->offset, 7848 block_group_rec->objectid, 7849 block_group_rec->flags); Within the .i it looks like this: if (!silent) fprintf( # 7836 "cmds-check.c" 3 4 stderr # 7836 "cmds-check.c" , "Chunk[%llu, %u, %llu]: length(%llu), offset(%llu), type(%llu) mismatch with block group[%llu, %u, %llu]: offset(%llu), objectid(%llu), flags(%llu)\n", Note that the very long line containing the format string was 191 chars long; looks like it triggered a transition to a new ordinary line map, since the default 7 bits of length, for a maximum column number of 127.