patch 8.0.0571: negative line number when using :z^ in an empty buffer commit https://github.com/vim/vim/commit/a364cdb648ae009fa7aa05382f5659335683d349 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Apr 20 21:12:30 2017 +0200 patch 8.0.0571: negative line number when using :z^ in an empty buffer Problem: The cursor line number becomes negative when using :z^ in an empty buffer. (neovim https://github.com/vim/vim/issues/6557) Solution: Correct the line number. Also reset the column.

--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -4664,6 +4664,8 @@ ex_z(exarg_T *eap)
 
     if (curs > curbuf->b_ml.ml_line_count)
 	curs = curbuf->b_ml.ml_line_count;
+    else if (curs < 1)
+	curs = 1;
 
     for (i = start; i <= end; i++)
     {
@@ -4686,7 +4688,11 @@ ex_z(exarg_T *eap)
 	}
     }
 
-    curwin->w_cursor.lnum = curs;
+    if (curwin->w_cursor.lnum != curs)
+    {
+	curwin->w_cursor.lnum = curs;
+	curwin->w_cursor.col = 0;
+    }
     ex_no_reprint = TRUE;
 }