This patch is for the google/gcc-4_7 branch.
This patch fixes a problem caused by the previous patch that removed
the code to copy children of a DIE referenced by a type unit.
> I don't believe that it's necessary to copy the children of the class
> declaration at all, and this patch simply removes the code that copies
> those children. If there's a reference in the type unit to one of the
> children of that class, that one child will get copied in as needed.
The problem was that it IS necessary to copy the children of a
non-declaration -- such as a DW_TAG_array_type. I've restored the
loop that calls clone_tree_partial, but placed it within a test
for is_declaration_die.
Bootstraps and passes regression tests. Also tested with parts of the
GDB testsuite, and is still able to build a large internal test case
that previously resulted in out-of-memory during compilation.
Google ref b/7041390.
2012-08-31 Cary Coutant <ccout...@google.com>
* gcc/dwarf2out.c (clone_tree_partial): Restore.
(copy_decls_walk): Call clone_tree_partial to copy children
of non-declaration DIEs.
Index: gcc/dwarf2out.c
===================================================================
--- gcc/dwarf2out.c (revision 190842)
+++ gcc/dwarf2out.c (working copy)
@@ -7745,6 +7745,40 @@ copy_ancestor_tree (dw_die_ref unit, dw_
return copy;
}
+/* Like clone_tree, but copy DW_TAG_subprogram DIEs as declarations.
+ Enter all the cloned children into the hash table decl_table. */
+
+static dw_die_ref
+clone_tree_partial (dw_die_ref die, htab_t decl_table)
+{
+ dw_die_ref c;
+ dw_die_ref clone;
+ struct decl_table_entry *entry;
+ void **slot;
+
+ if (die->die_tag == DW_TAG_subprogram)
+ clone = clone_as_declaration (die);
+ else
+ clone = clone_die (die);
+
+ slot = htab_find_slot_with_hash (decl_table, die,
+ htab_hash_pointer (die), INSERT);
+ /* Assert that DIE isn't in the hash table yet. If it would be there
+ before, the ancestors would be necessarily there as well, therefore
+ clone_tree_partial wouldn't be called. */
+ gcc_assert (*slot == HTAB_EMPTY_ENTRY);
+ entry = XCNEW (struct decl_table_entry);
+ entry->orig = die;
+ entry->copy = clone;
+ *slot = entry;
+
+ if (die->die_tag != DW_TAG_subprogram)
+ FOR_EACH_CHILD (die, c,
+ add_child_die (clone, clone_tree_partial (c, decl_table)));
+
+ return clone;
+}
+
/* Walk the DIE and its children, looking for references to incomplete
or trivial types that are unmarked (i.e., that are not in the current
type_unit). */
@@ -7792,6 +7826,16 @@ copy_decls_walk (dw_die_ref unit, dw_die
entry->copy = copy;
*slot = entry;
+ /* If TARG is not a declaration DIE, we need to copy its
+ children. */
+ if (!is_declaration_die (targ))
+ {
+ FOR_EACH_CHILD (
+ targ, c,
+ add_child_die (copy,
+ clone_tree_partial (c, decl_table)));
+ }
+
/* Make sure the cloned tree is marked as part of the
type unit. */
mark_dies (copy);
