diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index 0a94734..eddc8c5 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -740,6 +740,22 @@
 
   CheckDefFailure(['var lines =<< trim END X', 'END'], 'E488:')
   CheckDefFailure(['var lines =<< trim END " comment', 'END'], 'E488:')
+
+  lines =<< trim [END]
+      def Func()
+        var&lines =<< trim END
+        x
+        x
+        x
+        x
+        x
+        x
+        x
+        x
+      enddef
+      call Func()
+  [END]
+  CheckScriptFailure(lines, 'E990:')
 enddef
 
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker
diff --git a/src/version.c b/src/version.c
index fe73a92..7205343 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1760,
+/**/
     1759,
 /**/
     1758,
diff --git a/src/vim9compile.c b/src/vim9compile.c
index d505ca6..e4f3a90 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -4360,7 +4360,7 @@
 
     for (;;)
     {
-	if (cctx->ctx_lnum == cctx->ctx_ufunc->uf_lines.ga_len)
+	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len - 1)
 	    return NULL;
 	++cctx->ctx_lnum;
 	p = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];