diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index a92a60b..6bbbc36 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -681,6 +681,16 @@
       assert_equal('done', Partial())
   END
   CheckDefAndScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+      def Func(b: bool)
+      enddef
+      var Ref: func = function(Func, [true])
+      assert_equal('func()', typename(Ref))
+      Ref()
+  END
+  CheckScriptSuccess(lines)
 enddef
 
 def Test_assignment_list_any_index()
diff --git a/src/userfunc.c b/src/userfunc.c
index 404f85b..4234681 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -3148,7 +3148,8 @@
 	    argvars = argv;
 	    argcount = partial->pt_argc + argcount_in;
 
-	    if (funcexe->check_type != NULL)
+	    if (funcexe->check_type != NULL
+				     && funcexe->check_type->tt_argcount != -1)
 	    {
 		// Now funcexe->check_type is missing the added arguments, make
 		// a copy of the type with the correction.
diff --git a/src/version.c b/src/version.c
index 10231ab..060c2e7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3107,
+/**/
     3106,
 /**/
     3105,