diff --git a/src/ChangeLog b/src/ChangeLog
index 2e3b465e96e..5759d155580 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2014-06-02  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+	* callproc.c (call_process): Don't check read-only if we don't insert
+	anything (bug#17666).
+
 2014-06-02  Eli Zaretskii  <eliz@gnu.org>
 
 	* dispnew.c (update_frame_with_menu): Set display_completed.
diff --git a/src/callproc.c b/src/callproc.c
index 9e60ba11bcf..7ba3e398b41 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -826,8 +826,10 @@ call_process (ptrdiff_t nargs, Lisp_Object *args, int filefd,
 	  /* Now NREAD is the total amount of data in the buffer.  */
 	  immediate_quit = 0;
 
-	  if (NILP (BVAR (current_buffer, enable_multibyte_characters))
-	      && ! CODING_MAY_REQUIRE_DECODING (&process_coding))
+	  if (!nread)
+	    ;
+	  else if (NILP (BVAR (current_buffer, enable_multibyte_characters))
+		   && ! CODING_MAY_REQUIRE_DECODING (&process_coding))
 	    insert_1_both (buf, nread, nread, 0, 1, 0);
 	  else
 	    {			/* We have to decode the input.  */
@@ -835,6 +837,7 @@ call_process (ptrdiff_t nargs, Lisp_Object *args, int filefd,
 	      ptrdiff_t count1 = SPECPDL_INDEX ();
 
 	      XSETBUFFER (curbuf, current_buffer);
+	      /* FIXME: Call signal_after_change!  */
 	      prepare_to_modify_buffer (PT, PT, NULL);
 	      /* We cannot allow after-change-functions be run
 		 during decoding, because that might modify the