With this test, build_base_path was crashing because it (reasonably)
assumed that if we're in a constructor with virtual bases, we can look
at current_in_charge_parm. But we can't in a template, even when we've
cleared processing_template_decl for the sake of
fold_non_dependent_expr. So don't try.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit b27a03c5dcd721810269a876fd7f91e0d5a068ba
Author: Jason Merrill <ja...@redhat.com>
Date: Tue Nov 8 13:09:24 2011 -0500
PR c++/51029
* class.c (build_base_path): Don't ICE in fold_non_dependent_expr.
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index f10a749..d2cf63c 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -359,6 +359,11 @@ build_base_path (enum tree_code code,
V_BINFO. That offset is an entry in D_BINFO's vtable. */
tree v_offset;
+ /* In a constructor template, current_in_charge_parm isn't set,
+ and we might end up here via fold_non_dependent_expr. */
+ if (fixed_type_p < 0 && !(cfun && current_in_charge_parm))
+ fixed_type_p = 0;
+
if (fixed_type_p < 0 && in_base_initializer)
{
/* In a base member initializer, we cannot rely on the
diff --git a/gcc/testsuite/g++.dg/template/virtual1.C b/gcc/testsuite/g++.dg/template/virtual1.C
new file mode 100644
index 0000000..ee86bf3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/virtual1.C
@@ -0,0 +1,14 @@
+// PR c++/51029
+
+struct A
+{
+ void foo();
+};
+
+struct B : virtual A
+{
+ template<int> B()
+ {
+ foo();
+ }
+};
