diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index a7ab2bd2887..72bdf869b55 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -22120,7 +22120,16 @@ resolve_overloaded_unification (tree tparms,
 	  if (subargs != error_mark_node
 	      && !any_dependent_template_arguments_p (subargs))
 	    {
-	      elem = TREE_TYPE (instantiate_template (fn, subargs, tf_none));
+	      fn = instantiate_template (fn, subargs, tf_none);
+	      if (undeduced_auto_decl (fn))
+		{
+		  /* Instantiate the function to deduce its return type.  */
+		  ++function_depth;
+		  instantiate_decl (fn, /*defer*/false, /*class*/false);
+		  --function_depth;
+		}
+
+	      elem = TREE_TYPE (fn);
 	      if (try_one_overload (tparms, targs, tempargs, parm,
 				    elem, strict, sub_strict, addr_p, explain_p)
 		  && (!goodfn || !same_type_p (goodfn, elem)))
diff --git a/gcc/testsuite/g++.dg/cpp1y/auto-fn60.C b/gcc/testsuite/g++.dg/cpp1y/auto-fn60.C
new file mode 100644
index 00000000000..575abafbae5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/auto-fn60.C
@@ -0,0 +1,11 @@
+// PR c++/64194
+// { dg-do compile { target c++14 } }
+
+template <typename T> void g(void (*)(T)) { }
+
+template <typename> auto id(int) { }
+template <typename> auto id(char) { return 0; }
+
+int main() {
+  g(id<int>);
+}