diff --git a/src/fileio.c b/src/fileio.c
index 39e356f..9380953 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2251,8 +2251,9 @@
 			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;
 			    }