https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64928
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2015-02-09 Ever confirmed|0 |1 --- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> --- Ok, so the memory is used by out-of-SSA it seems #5 0x0000000000c9eebc in coalesce_ssa_name () at /space/rguenther/src/svn/gcc-4_9-branch/gcc/tree-ssa-coalesce.c:1330 1330 graph = build_ssa_conflict_graph (liveinfo); (gdb) p *cl->list.htab $10 = {entries = 0x2b19b30, size = 524287, n_elements = 77146, n_deleted = 0, searches = 122189, collisions = 6508, size_prime_index = 16} where we malloc(!) 77146 entries of size 12. But of course bad is the conflict graph with 76063 bitmaps eating up around 1GB of memory for the first testcase (and function ___H__23__23_u8vector_2d__3e_object). That's likely caused by the change to more aggressively coalesce anonymous SSA names.