patch 8.0.0227: crash with ff=dos when first line in file has no CR commit https://github.com/vim/vim/commit/2aa5f696b91a51f29873e340de4bdc182e1e8dd4 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Jan 24 15:46:48 2017 +0100 patch 8.0.0227: crash with ff=dos when first line in file has no CR Problem: Crash when 'fileformat' is forced to "dos" and the first line in the file is empty and does not have a CR character. Solution: Don't check for CR before the start of the buffer.

--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2251,8 +2251,9 @@ rewind_retry:
 			len = (colnr_T)(ptr - line_start + 1);
 			if (fileformat == EOL_DOS)
 			{
-			    if (ptr[-1] == CAR)	/* remove CR */
+			    if (ptr > line_start && ptr[-1] == CAR)
 			    {
+				/* remove CR before NL */
 				ptr[-1] = NUL;
 				--len;
 			    }