Set members of the struct coding_system before accessing them (bug#9910,9911,9912).

src/ChangeLog

+2011-11-07  Kenichi Handa  <handa@m17n.org>
+
+	* coding.c (coding_set_destination): Check coding->src_pos only
+	when coding->src_object is a buffer (bug#9910).
+
+	* process.c (send_process): Set the member src_multibyte of coding
+	to 0 (bug#9911) when sending a unibyte text.
+
+	* callproc.c (Fcall_process): Set the member src_multibyte of
+	process_coding to 0 (bug#9912).
+
 2011-11-03  Eli Zaretskii  <eliz@gnu.org>
 
 	* xdisp.c (note_mouse_highlight): Initialize `area'.  (Bug#9947)

src/callproc.c

@@ -748,6 +748,7 @@ usage: (call-process PROGRAM &optional INFILE BUFFER DISPLAY &rest ARGS)  */)
 	val = raw_text_coding_system (val);
       setup_coding_system (val, &process_coding);
     }
+  process_coding.src_multibyte = 0;
 
   immediate_quit = 1;
   QUIT;

src/coding.c

@@ -1043,7 +1043,7 @@ coding_set_destination (struct coding_system *coding)
 {
   if (BUFFERP (coding->dst_object))
     {
-      if (coding->src_pos < 0)
+      if (BUFFERP (coding->src_object) && coding->src_pos < 0)
 	{
 	  coding->destination = BEG_ADDR + coding->dst_pos_byte - BEG_BYTE;
 	  coding->dst_bytes = (GAP_END_ADDR

src/process.c

@@ -5387,6 +5387,7 @@ send_process (volatile Lisp_Object proc, const char *volatile buf,
     }
   else
     {
+      coding->src_multibyte = 0;
       /* For sending a unibyte text, character code conversion should
 	 not take place but EOL conversion should.  So, setup raw-text
 	 or one of the subsidiary if we have not yet done it.  */