PR c++/86147 - wrong capture for template argument.

	* expr.c (mark_use): Look through NOP_EXPR.

From-SVN: r261676

gcc/cp/ChangeLog

 2018-06-15  Jason Merrill  <jason@redhat.com>
 
+	PR c++/86147 - wrong capture for template argument.
+	* expr.c (mark_use): Look through NOP_EXPR.
+
 	* name-lookup.c (do_pushtag): Don't look through complete types, but
 	don't add to them either.  Get context from current_binding_level.
 	* pt.c (tsubst_default_argument): Use push_to/pop_from_top_level.

gcc/cp/expr.c

@@ -186,12 +186,15 @@ mark_use (tree expr, bool rvalue_p, bool read_p,
 	    expr = convert_from_reference (r);
 	}
       break;
-    default:
+
+    CASE_CONVERT:
+    case VIEW_CONVERT_EXPR:
       if (location_wrapper_p (expr))
-	{
-	  loc = EXPR_LOCATION (expr);
-	  recurse_op[0] = true;
-	}
+	loc = EXPR_LOCATION (expr);
+      recurse_op[0] = true;
+      break;
+
+    default:
       break;
     }
 

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-const9.C

+// PR c++/86147
+// { dg-do compile { target c++11 } }
+
+template <class T, T N> struct X { };
+
+struct A { static constexpr int value = 0; };
+
+template<class C>
+void foo() {
+    constexpr int N = C::value;
+    auto f = [&]{  X<int, N> a; };
+}
+
+int main() { 
+    foo<A>();
+    return 0;
+}