Attached is the patch to avoid the ICE that Kai posted below
with the test case Marek asked for in his response. I didn't
see any further followup on the list.
https://gcc.gnu.org/ml/gcc-patches/2015-05/msg02325.html
Martin
gcc/testsuite/ChangeLog:
2016-01-19 Martin Sebor <mse...@redhat.com>
PR c++/59759
* gcc/testsuite/g++.dg/template/pr59759.C: New test.
gcc/cp/ChangeLog:
2015-05-26 Kai Tietz <ktiet...@googlemail.com>
PR c++/69277
* pt.c (unify): Don't ICE on VAR_DECL.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 6062ebe..3361796 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -19928,11 +19928,11 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
return unify_template_argument_mismatch (explain_p, parm, arg);
case VAR_DECL:
- /* A non-type template parameter that is a variable should be a
+ /* A non-type template parameter that is a variable should be
an integral constant, in which case, it whould have been
- folded into its (constant) value. So we should not be getting
- a variable here. */
- gcc_unreachable ();
+ folded into its (constant) value. So we should not see
+ a variable here except for ill-formed programs. */
+ return unify_template_argument_mismatch (explain_p, parm, arg);
case TYPE_ARGUMENT_PACK:
case NONTYPE_ARGUMENT_PACK:
diff --git a/gcc/testsuite/g++.dg/template/pr59759.C b/gcc/testsuite/g++.dg/template/pr59759.C
new file mode 100644
index 0000000..c6a0b04
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/pr59759.C
@@ -0,0 +1,23 @@
+// PR c++/59759 - internal compiler error: in unify, using std::enable_if
+// on classes
+// { dg-do compile }
+
+template <class T>
+struct B { };
+
+template <class, class T>
+struct C {
+ typedef T U;
+};
+
+const int x = 0;
+
+// The default argument below is invalid for A<int>.
+template <class T, class C<B<T>, int>::U = x>
+struct A;
+
+template <class T>
+void f (A<T>*) {
+ A<int>* map; // { dg-error "not a class type" }
+ f (map); // { dg-error "no matching function" }
+}
