http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59890
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- Even with the obvious fix to val_reset Index: gcc/var-tracking.c =================================================================== --- gcc/var-tracking.c (revision 206808) +++ gcc/var-tracking.c (working copy) @@ -2501,7 +2501,8 @@ val_reset (dataflow_set *set, decl_or_va gcc_assert (var->n_var_parts == 1); - if (var->onepart == ONEPART_VALUE) + if (var->onepart == ONEPART_VALUE + && local_get_addr_cache != NULL) { rtx x = dv_as_value (dv); void **slot; I get during -m32 multilib x86_64 libjava build Program received signal SIGSEGV, Segmentation fault. vt_get_canonicalize_base (loc=0x0) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:1985 1985 || GET_CODE (loc) == AND) (gdb) bt #0 vt_get_canonicalize_base (loc=0x0) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:1985 #1 0x0000000000ba7db0 in local_get_addr_clear_given_value (v=<optimized out>, slot=0x1ab8c28, x=0x1a6bdc8) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:2484 #2 0x00000000008bfeec in pointer_map_traverse (pmap=0x0, fn=0x1ab8c28, data=0x1a6bdc8) at /space/rguenther/src/svn/trunk/gcc/pointer-set.c:269 #3 0x0000000000bb6612 in val_reset (set=set@entry=0x1ab74b8, dv=dv@entry=0x1a6bdc8) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:2522 #4 0x0000000000bba55c in val_resolve (set=set@entry=0x1ab74b8, val=0x1a6bdc8, loc=0x7ffff60b6b20, insn=insn@entry=0x7ffff4c07dc8) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:2597 #5 0x0000000000bbac6f in compute_bb_dataflow ( bb=<error reading variable: Unhandled dwarf expression opcode 0xfa>) at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:6695 #6 0x0000000000bbbfa9 in vt_find_locations () at /space/rguenther/src/svn/trunk/gcc/var-tracking.c:7047 Btw, this all is with Index: gcc/var-tracking.c =================================================================== --- gcc/var-tracking.c (revision 206808) +++ gcc/var-tracking.c (working copy) @@ -6934,12 +6935,12 @@ vt_find_locations (void) bool success = true; timevar_push (TV_VAR_TRACKING_DATAFLOW); - /* Compute reverse completion order of depth first search of the CFG + /* Compute reverse top sord order of the inverted CFG so that the data-flow runs faster. */ - rc_order = XNEWVEC (int, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); + rc_order = XNEWVEC (int, n_basic_blocks_for_fn (cfun)); bb_order = XNEWVEC (int, last_basic_block_for_fn (cfun)); - pre_and_rev_post_order_compute (NULL, rc_order, false); - for (i = 0; i < n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; i++) + int num = inverted_post_order_compute (rc_order); + for (i = 0; i < num; i++) bb_order[rc_order[i]] = i; free (rc_order); which provides a nice speedup for some testcases (inverted post-order is the correct order for a forward dataflow problem). static bool local_get_addr_clear_given_value (const void *v ATTRIBUTE_UNUSED, void **slot, void *x) { if (vt_get_canonicalize_base ((rtx)*slot) == x) *slot = NULL; return true; } if you do that again you have to guard against a cleared valued! (pointer-map does not allow removal) Index: gcc/var-tracking.c =================================================================== --- gcc/var-tracking.c (revision 206808) +++ gcc/var-tracking.c (working copy) @@ -2481,7 +2481,8 @@ static bool local_get_addr_clear_given_value (const void *v ATTRIBUTE_UNUSED, void **slot, void *x) { - if (vt_get_canonicalize_base ((rtx)*slot) == x) + if (*slot != NULL + && vt_get_canonicalize_base ((rtx)*slot) == x) *slot = NULL; return true; }