[RFA 4/5] Use ui_out_emit_tuple in more places in MI

[Tom Tromey <tom@tromey.com>]

This patch changes a few more spots in MI to use ui_out_emit_tuple.
These changes required the use of gdb::optional.

gdb/ChangeLog
2017-04-13  Tom Tromey  <tom@tromey.com>

	* mi/mi-main.c (print_variable_or_computed): Use ui_out_emit_tuple.
	* mi/mi-cmd-var.c (varobj_update_one): Use ui_out_emit_tuple.
	* mi/mi-cmd-stack.c (list_arg_or_local): Use ui_out_emit_tuple.
---
 gdb/ChangeLog         | 6 ++++++
 gdb/mi/mi-cmd-stack.c | 9 +++------
 gdb/mi/mi-cmd-var.c   | 7 +++----
 gdb/mi/mi-main.c      | 7 ++-----
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index ba91cdc..e972b4c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,11 @@
 2017-04-13  Tom Tromey  <tom@tromey.com>
 
+	* mi/mi-main.c (print_variable_or_computed): Use ui_out_emit_tuple.
+	* mi/mi-cmd-var.c (varobj_update_one): Use ui_out_emit_tuple.
+	* mi/mi-cmd-stack.c (list_arg_or_local): Use ui_out_emit_tuple.
+
+2017-04-13  Tom Tromey  <tom@tromey.com>
+
 	* tracepoint.c (tvariables_info_1)
 	(print_one_static_tracepoint_marker): Use ui_out_emit_tuple.
 
diff --git a/gdb/mi/mi-cmd-stack.c b/gdb/mi/mi-cmd-stack.c
index f288817..bd24e5b 100644
--- a/gdb/mi/mi-cmd-stack.c
+++ b/gdb/mi/mi-cmd-stack.c
@@ -34,6 +34,7 @@
 #include "extension.h"
 #include <ctype.h>
 #include "mi-parse.h"
+#include "common/gdb_optional.h"
 
 enum what_to_list { locals, arguments, all };
 
@@ -483,7 +484,6 @@ static void
 list_arg_or_local (const struct frame_arg *arg, enum what_to_list what,
 		   enum print_values values, int skip_unavailable)
 {
-  struct cleanup *old_chain;
   struct ui_out *uiout = current_uiout;
 
   gdb_assert (!arg->val || !arg->error);
@@ -507,10 +507,9 @@ list_arg_or_local (const struct frame_arg *arg, enum what_to_list what,
 					 TYPE_LENGTH (value_type (arg->val))))))
     return;
 
-  old_chain = make_cleanup (null_cleanup, NULL);
-
+  gdb::optional<ui_out_emit_tuple> tuple_emitter;
   if (values != PRINT_NO_VALUES || what == all)
-    make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
+    tuple_emitter.emplace (uiout, nullptr);
 
   string_file stb;
 
@@ -556,8 +555,6 @@ list_arg_or_local (const struct frame_arg *arg, enum what_to_list what,
 	stb.printf (_("<error reading variable: %s>"), error_message);
       uiout->field_stream ("value", stb);
     }
-
-  do_cleanups (old_chain);
 }
 
 /* Print a list of the objects for the frame FI in a certain form,
diff --git a/gdb/mi/mi-cmd-var.c b/gdb/mi/mi-cmd-var.c
index 0a4ed62..1a7e322 100644
--- a/gdb/mi/mi-cmd-var.c
+++ b/gdb/mi/mi-cmd-var.c
@@ -30,6 +30,7 @@
 #include "mi-getopt.h"
 #include "gdbthread.h"
 #include "mi-parse.h"
+#include "common/gdb_optional.h"
 
 extern unsigned int varobjdebug;		/* defined in varobj.c.  */
 
@@ -712,10 +713,10 @@ varobj_update_one (struct varobj *var, enum print_values print_values,
   for (i = 0; VEC_iterate (varobj_update_result, changes, i, r); ++i)
     {
       int from, to;
-      struct cleanup *cleanup = make_cleanup (null_cleanup, NULL);
 
+      gdb::optional<ui_out_emit_tuple> tuple_emitter;
       if (mi_version (uiout) > 1)
-	make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
+	tuple_emitter.emplace (uiout, nullptr);
       uiout->field_string ("name", varobj_get_objname (r->varobj));
 
       switch (r->status)
@@ -784,8 +785,6 @@ varobj_update_one (struct varobj *var, enum print_values print_values,
 	  VEC_free (varobj_p, r->newobj);
 	  r->newobj = NULL;	/* Paranoia.  */
 	}
-
-      do_cleanups (cleanup);
     }
   VEC_free (varobj_update_result, changes);
 }
diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
index d309ba3..7e225db 100644
--- a/gdb/mi/mi-main.c
+++ b/gdb/mi/mi-main.c
@@ -2656,7 +2656,6 @@ mi_cmd_ada_task_info (const char *command, char **argv, int argc)
 static void
 print_variable_or_computed (const char *expression, enum print_values values)
 {
-  struct cleanup *old_chain;
   struct value *val;
   struct type *type;
   struct ui_out *uiout = current_uiout;
@@ -2670,9 +2669,9 @@ print_variable_or_computed (const char *expression, enum print_values values)
   else
     val = evaluate_expression (expr.get ());
 
-  old_chain = make_cleanup (null_cleanup, NULL);
+  gdb::optional<ui_out_emit_tuple> tuple_emitter;
   if (values != PRINT_NO_VALUES)
-    make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
+    tuple_emitter.emplace (uiout, nullptr);
   uiout->field_string ("name", expression);
 
   switch (values)
@@ -2704,8 +2703,6 @@ print_variable_or_computed (const char *expression, enum print_values values)
       }
       break;
     }
-
-  do_cleanups (old_chain);
 }
 
 /* Implement the "-trace-frame-collected" command.  */
-- 
2.9.3