http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55792
--- Comment #20 from H.J. Lu <hjl.tools at gmail dot com> 2013-01-09 17:12:45 UTC --- we put the remapped block in line_table: #0 0x000000000101d8cf in get_combined_adhoc_loc (set=0x7ffff7ffc000, locus=968541695, data=0x7fffe8d6fe60) at /export/gnu/import/git/gcc/libcpp/line-map.c:146 #1 0x00000000009f839d in gimple_set_block (g=0x7fffe8d759b0, block=0x7fffe8d6fe60) at /export/gnu/import/git/gcc/gcc/gimple.h:1226 #2 0x0000000000a016fd in remap_gimple_stmt (stmt=0x7fffe910e0a0, id=0x7fffffffd900) at /export/gnu/import/git/gcc/gcc/tree-inline.c:1473 #3 0x0000000000a01a04 in copy_bb (id=0x7fffffffd900, bb=0x7fffe910c888, frequency_scale=1000000, count_scale=1779) at /export/gnu/import/git/gcc/gcc/tree-inline.c:1539 #4 0x0000000000a03f56 in copy_cfg_body (id=0x7fffffffd900, count=48912247, frequency_scale=1000000, entry_block_map=0x7ffff138aaf8, exit_block_map=0x7fffe8d58270, blocks_to_copy=0x0, new_entry=0x0) at /export/gnu/import/git/gcc/gcc/tree-inline.c:2259 #5 0x0000000000a047fa in copy_body (id=0x7fffffffd900, count=48912247, frequency_scale=1000000, entry_block_map=0x7ffff138aaf8, exit_block_map=0x7fffe8d58270, blocks_to_copy=0x0, new_entry=0x0) at /export/gnu/import/git/gcc/gcc/tree-inline.c:2457 #6 0x0000000000a0881e in expand_call_inline (bb=0x7ffff138aaf8, stmt=0x7ffff1390980, id=0x7fffffffd900) at /export/gnu/import/git/gcc/gcc/tree-inline.c:4041 #7 0x0000000000a08c6f in gimple_expand_calls_inline (bb=0x7ffff138aaf8, id=0x7fffffffd900) at /export/gnu/import/git/gcc/gcc/tree-inline.c:4147 But tree node in line_table is ignored by GC.