Hi,
in this ICE on invalid regression we emit a sensible error message about
the duplicate base and then we ICE when we process the function, because
TYPE_VFIELD (type) is null in build_vfield_ref. My changes just check
for the offending situation and return early from build_base_path
(fold_build_pointer_plus would crash for an error_mark_node).
Tested x86_64-linux.
Thanks,
Paolo.
////////////////////
/cp
2014-01-31 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/59082
* class.c (build_vfield_ref): Early return error_mark_node if
TYPE_VFIELD (type) is null.
(build_base_path): Check return value of build_vfield_ref.
/testsuite
2014-01-31 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/59082
* g++.dg/inherit/crash4.C: New.
Index: cp/class.c
===================================================================
--- cp/class.c (revision 207336)
+++ cp/class.c (working copy)
@@ -431,6 +431,9 @@ build_base_path (enum tree_code code,
v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
complain),
TREE_TYPE (TREE_TYPE (expr)));
+
+ if (v_offset == error_mark_node)
+ return error_mark_node;
v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD
(v_binfo));
v_offset = build1 (NOP_EXPR,
@@ -625,7 +628,9 @@ build_vfield_ref (tree datum, tree type)
{
tree vfield, vcontext;
- if (datum == error_mark_node)
+ if (datum == error_mark_node
+ /* Can happen in case of duplicate base types (c++/59082). */
+ || !TYPE_VFIELD (type))
return error_mark_node;
/* First, convert to the requested type. */
Index: testsuite/g++.dg/inherit/crash4.C
===================================================================
--- testsuite/g++.dg/inherit/crash4.C (revision 0)
+++ testsuite/g++.dg/inherit/crash4.C (working copy)
@@ -0,0 +1,10 @@
+// PR c++/59082
+
+struct A {};
+
+struct B : virtual A, A {}; // { dg-error "duplicate base type" }
+
+A foo(const B &b)
+{
+ return b;
+}
