Missing do_cleanups in ada_make_symbol_completion_list.

This results in an internal-warning when trying the completion
when in Ada mode:

    (gdb) b simple<TAB>
    /[...]/cleanups.c:265: internal-warning: restore_my_cleanups has found a stale cleanup
    A problem internal to GDB has been detected,
    further debugging may prove unreliable.
    Quit this debugging session? (y or n)

gdb/ChangeLog:

        * ada-lang.c (ada_make_symbol_completion_list): Make sure
        all cleanups are done before returning from this function.

gdb/testsuite/ChangeLog:

        * gdb.ada/complete.exp: Add test verifying completion using
        the "tab" key.

gdb/ChangeLog

@@ -1,3 +1,8 @@
+2013-05-16  Joel Brobecker  <brobecker@adacore.com>
+
+	* ada-lang.c (ada_make_symbol_completion_list): Make sure
+	all cleanups are done before returning from this function.
+
 2013-05-15  Joel Brobecker  <brobecker@adacore.com>
 
 	* utils.h: #include "exceptions.h".

gdb/ada-lang.c

@@ -5841,6 +5841,7 @@ ada_make_symbol_completion_list (const char *text0, const char *word,
   struct block *b, *surrounding_static_block = 0;
   int i;
   struct block_iterator iter;
+  struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
 
   gdb_assert (code == TYPE_CODE_UNDEF);
 
@@ -5941,6 +5942,7 @@ ada_make_symbol_completion_list (const char *text0, const char *word,
     }
   }
 
+  do_cleanups (old_chain);
   return completions;
 }
 

gdb/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2013-05-16  Joel Brobecker  <brobecker@adacore.com>
+
+	* gdb.ada/complete.exp: Add test verifying completion using
+	the "tab" key.
+
 2013-05-15  Pedro Alves  <palves@redhat.com>
 
 	* gdb.base/fixsection.c: Remove attribution.

gdb/testsuite/gdb.ada/complete.exp

@@ -175,4 +175,19 @@ test_gdb_complete "pck." \
 test_gdb_complete "<pck__my" \
                   "p <pck__my_global_variable>"
 
-
+# Very simple completion, but using the interactive form, this time.
+# The verification we are trying to make involves the event loop,
+# and using the "complete" command is not sufficient to reproduce
+# the original problem.
+set test "interactive complete 'print some'"
+send_gdb "print some\t"
+gdb_test_multiple "" "$test" {
+    -re "^print some_local_variable $" {
+        send_gdb "\n"
+        gdb_test_multiple "" "$test" {
+            -re " = 1$eol$gdb_prompt $" {
+                pass "$test"
+            }
+        }
+    }
+}