pt.c (tsubst_copy_and_build): Get LAMBDA_EXPR_RETURN_TYPE from the instantiated closure.

	* pt.c (tsubst_copy_and_build) [LAMBDA_EXPR]: Get
	LAMBDA_EXPR_RETURN_TYPE from the instantiated closure.

From-SVN: r233955

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index e68382c3440c686b66b57cd411573b262fb71d47..2785135c8c71cf41a1aa054220eabbea5fbc9658 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2016-03-03  Jason Merrill  <jason@redhat.com>
 
+       * pt.c (tsubst_copy_and_build) [LAMBDA_EXPR]: Get
+       LAMBDA_EXPR_RETURN_TYPE from the instantiated closure.
+
        PR c++/67164
        * pt.c (copy_template_args): New.
        (tsubst_pack_expansion): Use it.

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index c5b92013830bd539117522bf938bd60411080a73..e8cd7367f5635058098fae553730b2dcc01fbc33 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -17103,8 +17103,6 @@ tsubst_copy_and_build (tree t,
        else
          gcc_unreachable ();
        LAMBDA_EXPR_EXTRA_SCOPE (r) = scope;
-       LAMBDA_EXPR_RETURN_TYPE (r)
-         = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
 
        gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
                    && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
@@ -17115,6 +17113,9 @@ tsubst_copy_and_build (tree t,
           declaration of the op() for later calls to lambda_function.  */
        complete_type (type);
 
+       if (tree fn = lambda_function (type))
+         LAMBDA_EXPR_RETURN_TYPE (r) = TREE_TYPE (TREE_TYPE (fn));
+
        LAMBDA_EXPR_THIS_CAPTURE (r) = NULL_TREE;
 
        insert_pending_capture_proxies ();

diff --git a/gcc/testsuite/g++.dg/cpp1y/lambda-generic-trailing1.C b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-trailing1.C
new file mode 100644 (file)
index 0000000..96755b1
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-trailing1.C
@@ -0,0 +1,12 @@
+// { dg-do compile { target c++14 } }
+
+template <class T>
+void f()
+{
+  auto lam = [](auto a)->decltype(++a) { return a; };
+}
+
+int main()
+{
+  f<int>();
+}