diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index da499c9..a2e53ad 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -7347,6 +7347,11 @@
     char_u	*arg = eap->arg;
     char_u	*p;
 
+    if (!isdigit(*arg))
+    {
+	semsg(_(e_invarg2), arg);
+	return;
+    }
     w = getdigits(&arg);
     arg = skipwhite(arg);
     p = arg;
diff --git a/src/testdir/test_excmd.vim b/src/testdir/test_excmd.vim
index 150e258..f27b385 100644
--- a/src/testdir/test_excmd.vim
+++ b/src/testdir/test_excmd.vim
@@ -327,6 +327,9 @@
 " Test for the :winsize command
 func Test_winsize_cmd()
   call assert_fails('winsize 1', 'E465:')
+  call assert_fails('winsize 1 x', 'E465:')
+  call assert_fails('win_getid(1)', 'E475: Invalid argument: _getid(1)')
+  " Actually changing the window size would be flaky.
 endfunc
 
 " Test for the :redir command
diff --git a/src/version.c b/src/version.c
index e8c286b..fb3a50a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2469,
+/**/
     2468,
 /**/
     2467,