MI varobj/testing tweaks

[Daniel Jacobowitz <drow at false dot org>]

Some things I found while testing a queued patch after Vlad's and
Nick's recent changes.  It had a char[0], for which num_children
got left as -1.  Which is bad, because (A) we don't document any
useful meaning for a negative number of children, and (B) integer
promotion turns that into an infinite loop.

This also fixes a race condition in mi_runto_helper.  If it sees
"^running\r\n(gdb)\r\n" when it expects to be waiting for ^stopped,
it will issue a FAIL and get out of synch.

Tested x86_64-pc-linux-gnu, checked in.

-- 
Daniel Jacobowitz
CodeSourcery

2007-01-04  Daniel Jacobowitz  <dan@codesourcery.com>

	* varobj.c (varobj_list_children): Stop if the number of children is
	unknown.
	(c_number_of_children): Report no children for zero sized arrays.

2007-01-04  Daniel Jacobowitz  <dan@codesourcery.com>

	* lib/mi-support.exp (mi_runto_helper): Expect two prompts
	when continuing.

Index: varobj.c
===================================================================
RCS file: /cvs/src/src/gdb/varobj.c,v
retrieving revision 1.71
diff -u -p -r1.71 varobj.c
--- varobj.c	4 Jan 2007 19:27:50 -0000	1.71
+++ varobj.c	4 Jan 2007 21:47:38 -0000
@@ -685,6 +685,10 @@ varobj_list_children (struct varobj *var
   if (var->num_children == -1)
     var->num_children = number_of_children (var);
 
+  /* If that failed, give up.  */
+  if (var->num_children == -1)
+    return -1;
+
   /* If we're called when the list of children is not yet initialized,
      allocate enough elements in it.  */
   while (VEC_length (varobj_p, var->children) < var->num_children)
@@ -1711,7 +1715,9 @@ c_number_of_children (struct varobj *var
 	  && TYPE_ARRAY_UPPER_BOUND_TYPE (type) != BOUND_CANNOT_BE_DETERMINED)
 	children = TYPE_LENGTH (type) / TYPE_LENGTH (target);
       else
-	children = -1;
+	/* If we don't know how many elements there are, don't display
+	   any.  */
+	children = 0;
       break;
 
     case TYPE_CODE_STRUCT:
Index: testsuite/lib/mi-support.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/lib/mi-support.exp,v
retrieving revision 1.37
diff -u -p -r1.37 mi-support.exp
--- testsuite/lib/mi-support.exp	4 Jan 2007 20:12:15 -0000	1.37
+++ testsuite/lib/mi-support.exp	4 Jan 2007 21:49:54 -0000
@@ -880,8 +880,17 @@ proc mi_runto_helper {func run_or_contin
   if {$run_or_continue == "run"} {
       mi_run_cmd
   } else {
-    send_gdb "000-exec-continue\n"
+      send_gdb "000-exec-continue\n"
+      gdb_expect {
+	  -re "000\\^running\r\n${mi_gdb_prompt}" {
+	  }
+	  timeout {
+	    fail "$test"
+	    return -1
+	  }
+      }
   }
+
   gdb_expect {
     -re ".*000\\*stopped,thread-id=\"$decimal\",frame=\{addr=\"$hex\",func=\"$func\",args=\(\\\[.*\\\]\|\{.*\}\),file=\".*\",fullname=\"${fullname_syntax}.*\",line=\"\[0-9\]*\"\}\r\n$mi_gdb_prompt$" {
       pass "$test"