diff --git a/src/eval.c b/src/eval.c
index 9091f79..55d61e7 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -26440,8 +26440,10 @@
     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'S')
     {
 	/* vim_strsave_shellescape() needs a NUL terminated string. */
+	c = (*fnamep)[*fnamelen];
 	(*fnamep)[*fnamelen] = NUL;
 	p = vim_strsave_shellescape(*fnamep, FALSE, FALSE);
+	(*fnamep)[*fnamelen] = c;
 	if (p == NULL)
 	    return -1;
 	vim_free(*bufp);
diff --git a/src/testdir/test105.in b/src/testdir/test105.in
index 9921d7e..4cc0261 100644
--- a/src/testdir/test105.in
+++ b/src/testdir/test105.in
@@ -36,6 +36,7 @@
 :Put fnamemodify('abc''%''def',    ':S'      )
 :Put fnamemodify("abc\ndef",       ':S'      )
 :Put expand('%:r:S') == shellescape(expand('%:r'))
+:Put join([expand('%:r'), expand('%:r:S'), expand('%')], ',')
 :set shell=tcsh
 :Put fnamemodify("abc\ndef",       ':S'      )
 :$put ='vim: ts=8'
diff --git a/src/testdir/test105.ok b/src/testdir/test105.ok
index 584f0fe..6642bfe 100644
--- a/src/testdir/test105.ok
+++ b/src/testdir/test105.ok
@@ -26,5 +26,6 @@
 fnamemodify('abc''%''def',    ':S'      )	'''abc''\''''%''\''''def'''
 fnamemodify("abc\ndef",       ':S'      )	'''abc^@def'''
 expand('%:r:S') == shellescape(expand('%:r'))	1
+join([expand('%:r'), expand('%:r:S'), expand('%')], ',')	'test105,''test105'',test105.in'
 fnamemodify("abc\ndef",       ':S'      )	'''abc\^@def'''
 vim: ts=8
diff --git a/src/version.c b/src/version.c
index 15b6d0d..4cd93d2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -749,6 +749,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1643,
+/**/
     1642,
 /**/
     1641,