diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 385cf3b4ae279b7007b01d5e57148547ebecfe47..6b8fecbac8e6430b48ef2a34d90b2197a67edbf9 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -3089,7 +3089,7 @@ append_command(char_u *cmd)
 
     STRCAT(IObuff, ": ");
     d = IObuff + STRLEN(IObuff);
-    while (*s != NUL && d - IObuff < IOSIZE - 7)
+    while (*s != NUL && d - IObuff + 5 < IOSIZE)
     {
 	if (enc_utf8 ? (s[0] == 0xc2 && s[1] == 0xa0) : *s == 0xa0)
 	{
@@ -3097,6 +3097,8 @@ append_command(char_u *cmd)
 	    STRCPY(d, "<a0>");
 	    d += 4;
 	}
+	else if (d - IObuff + (*mb_ptr2len)(s) + 1 >= IOSIZE)
+	    break;
 	else
 	    MB_COPY_CHAR(s, d);
     }
diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index 3f73d3da34950d8a4cfc1c5091b0db913faf75dc..c977a639fd59f3d6ec2d71c1062ee1a6189aeee6 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -842,3 +842,14 @@ func Test_buffers_lastused()
   bwipeout bufb
   bwipeout bufc
 endfunc
+
+" this was going over the end of IObuff
+func Test_report_error_with_composing()
+  let caught = 'no'
+  try
+    exe repeat('0', 987) .. "0\xdd\x80\xdd\x80\xdd\x80\xdd\x80"
+  catch /E492:/
+    let caught = 'yes'
+  endtry
+  call assert_equal('yes', caught)
+endfunc
\ No newline at end of file
diff --git a/src/version.c b/src/version.c
index bd442f5d6fcf63c9c4fdc509148678771459fd8e..5ceb369976427dde91f11baceb1bb77b1f242779 100644
--- a/src/version.c
+++ b/src/version.c
@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2271,
 /**/
     2270,
 /**/