http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55792
--- Comment #21 from Richard Biener <rguenth at gcc dot gnu.org> 2013-01-09
18:20:32 UTC ---
(In reply to comment #19)
> The BLOCK tree node is cleared by
>
> (gdb) bt
> #0 0x000000336b4882ee in __memset_sse2 () from /lib64/libc.so.6
> #1 0x0000000000545fdf in clear_marks ()
> at /export/gnu/import/git/gcc/gcc/ggc-page.c:1815
> #2 0x0000000000546621 in ggc_collect ()
> at /export/gnu/import/git/gcc/gcc/ggc-page.c:2086
> #3 0x00000000008ad816 in execute_todo (flags=2102)
> at /export/gnu/import/git/gcc/gcc/passes.c:2023
> #4 0x00000000008ae175 in execute_one_pass (pass=0x17b9c70)
> at /export/gnu/import/git/gcc/gcc/passes.c:2349
> #5 0x00000000008ae2da in execute_pass_list (pass=0x17b9c70)
> at /export/gnu/import/git/gcc/gcc/passes.c:2383
> #6 0x00000000008ae30b in execute_pass_list (
> pass=0x16d07e0 <pass_all_optimizations>)
> at /export/gnu/import/git/gcc/gcc/passes.c:2384
> #7 0x00000000005da366 in expand_function (node=0x7ffff16f5378)
> at /export/gnu/import/git/gcc/gcc/cgraphunit.c:1641
> #8 0x00000000005da821 in expand_all_functions ()
> at /export/gnu/import/git/gcc/gcc/cgraphunit.c:1745
> #9 0x00000000005db2ab in compile ()
> at /export/gnu/import/git/gcc/gcc/cgraphunit.c:2043
> #10 0x000000000053c60a in lto_main ()
> at /export/gnu/import/git/gcc/gcc/lto/lto.c:3390
> #11 0x0000000000999401 in compile_file ()
> ---Type <return> to continue, or q <return> to quit---
> at /export/gnu/import/git/gcc/gcc/toplev.c:545
> #12 0x000000000099b3e4 in do_compile ()
> at /export/gnu/import/git/gcc/gcc/toplev.c:1878
> #13 0x000000000099b54f in toplev_main (argc=28, argv=0x7fffffffdc78)
> at /export/gnu/import/git/gcc/gcc/toplev.c:1954
> #14 0x0000000000fff958 in main (argc=28, argv=0x7fffffffdc78)
> at /export/gnu/import/git/gcc/gcc/main.c:36
> (gdb)
>
> When we remap a block:
> static void
> remap_block (tree *block, copy_body_data *id)
> {
> tree old_block;
> tree new_block;
>
> /* Make the new block. */
> old_block = *block;
> new_block = make_node (BLOCK);
> TREE_USED (new_block) = TREE_USED (old_block);
> BLOCK_ABSTRACT_ORIGIN (new_block) = old_block;
> BLOCK_SOURCE_LOCATION (new_block) = BLOCK_SOURCE_LOCATION (old_block);
> BLOCK_NONLOCALIZED_VARS (new_block)
> = vec_safe_copy (BLOCK_NONLOCALIZED_VARS (old_block));
> *block = new_block;
>
> /* Remap its variables. */
> BLOCK_VARS (new_block) = remap_decls (BLOCK_VARS (old_block),
> &BLOCK_NONLOCALIZED_VARS (new_block),
> id);
>
> we didn't register it with GC root.
Remapped blocks are supposed to be linked into the BLOCK tree of the
destination. What's the backtrace of this remap_block?
