[PATCH 4/6] Constify some parameters in the varobj code

[Simon Marchi <simon.marchi@ericsson.com>]

To make it clear that some functions should not modify the variable
object, this patch adds the const qualifier where it makes sense to some
struct varobj * parameters. Most getters should take a const pointer to
guarantee they don't modify the object.

Unfortunately, I couldn't add it to some callbacks (such as name_of_child).
In the C implementation, they call c_describe_child, which calls
varobj_get_path_expr. varobj_get_path_expr needs to modify the object in
order to cache the computed value. It therefore can't take a const
pointer, and it affects the whole call chain. I suppose that's where you
would use a "mutable" in C++.

I did that to make sure there was no other cases like the one fixed in
the previous patch. I don't think it can hurt.

gdb/ChangeLog:

	* ada-varobj.c (ada_number_of_children): Constify struct varobj *
	parameter.
	(ada_name_of_variable): Same.
	(ada_path_expr_of_child): Same.
	(ada_value_of_variable): Same.
	(ada_value_is_changeable_p): Same.
	(ada_value_has_mutated): Same.
	* c-varobj.c (varobj_is_anonymous_child): Same.
	(c_is_path_expr_parent): Same.
	(c_number_of_children): Same.
	(c_name_of_variable): Same.
	(c_path_expr_of_child): Same.
	(get_type): Same.
	(c_value_of_variable): Same.
	(cplus_number_of_children): Same.
	(cplus_name_of_variable): Same.
	(cplus_path_expr_of_child): Same.
	(cplus_value_of_variable): Same.
	* jv-varobj.c (java_number_of_children): Same.
	(java_name_of_variable): Same.
	(java_path_expr_of_child): Same.
	(java_value_of_variable): Same.
	* varobj.c (number_of_children): Same.
	(name_of_variable): Same.
	(is_root_p): Same.
	(varobj_ensure_python_env): Same.
	(varobj_get_objname): Same.
	(varobj_get_expression): Same.
	(varobj_get_display_format): Same.
	(varobj_get_display_hint): Same.
	(varobj_has_more): Same.
	(varobj_get_thread_id): Same.
	(varobj_get_frozen): Same.
	(dynamic_varobj_has_child_method): Same.
	(varobj_get_gdb_type): Same.
	(is_path_expr_parent): Same.
	(varobj_default_is_path_expr_parent): Same.
	(varobj_get_language): Same.
	(varobj_get_attributes): Same.
	(varobj_is_dynamic_p): Same.
	(varobj_get_child_range): Same.
	(varobj_value_has_mutated): Same.
	(varobj_get_value_type): Same.
	(number_of_children): Same.
	(name_of_variable): Same.
	(check_scope): Same.
	(varobj_editable_p): Same.
	(varobj_value_is_changeable_p): Same.
	(varobj_floating_p): Same.
	(varobj_default_value_is_changeable_p): Same.
	* varobj.h (struct lang_varobj_ops): Consitfy some struct varobj *
	parameters.
	(varobj_get_objname): Constify struct varobj * parameter.
	(varobj_get_expression): Same.
	(varobj_get_thread_id): Same.
	(varobj_get_frozen): Same.
	(varobj_get_child_range): Same.
	(varobj_get_display_hint): Same.
	(varobj_get_gdb_type): Same.
	(varobj_get_language): Same.
	(varobj_get_attributes): Same.
	(varobj_editable_p): Same.
	(varobj_floating_p): Same.
	(varobj_has_more): Same.
	(varobj_is_dynamic_p): Same.
	(varobj_ensure_python_env): Same.
	(varobj_default_value_is_changeable_p): Same.
	(varobj_value_is_changeable_p): Same.
	(varobj_get_value_type): Same.
	(varobj_is_anonymous_child): Same.
	(varobj_value_get_print_value): Same.
	(varobj_default_is_path_expr_parent): Same.
---
 gdb/ada-varobj.c | 12 ++++++------
 gdb/c-varobj.c   | 22 ++++++++++-----------
 gdb/jv-varobj.c  |  8 ++++----
 gdb/varobj.c     | 60 ++++++++++++++++++++++++++++----------------------------
 gdb/varobj.h     | 56 ++++++++++++++++++++++++++--------------------------
 5 files changed, 79 insertions(+), 79 deletions(-)

diff --git a/gdb/ada-varobj.c b/gdb/ada-varobj.c
index 690ee49..3ecac9d 100644
--- a/gdb/ada-varobj.c
+++ b/gdb/ada-varobj.c
@@ -906,13 +906,13 @@ ada_varobj_get_value_of_variable (struct value *value,
 /* Ada specific callbacks for VAROBJs.  */
 
 static int
-ada_number_of_children (struct varobj *var)
+ada_number_of_children (const struct varobj *var)
 {
   return ada_varobj_get_number_of_children (var->value, var->type);
 }
 
 static char *
-ada_name_of_variable (struct varobj *parent)
+ada_name_of_variable (const struct varobj *parent)
 {
   return c_varobj_ops.name_of_variable (parent);
 }
@@ -925,7 +925,7 @@ ada_name_of_child (struct varobj *parent, int index)
 }
 
 static char*
-ada_path_expr_of_child (struct varobj *child)
+ada_path_expr_of_child (const struct varobj *child)
 {
   struct varobj *parent = child->parent;
   const char *parent_path_expr = varobj_get_path_expr (parent);
@@ -952,7 +952,7 @@ ada_type_of_child (struct varobj *parent, int index)
 }
 
 static char *
-ada_value_of_variable (struct varobj *var, enum varobj_display_formats format)
+ada_value_of_variable (const struct varobj *var, enum varobj_display_formats format)
 {
   struct value_print_options opts;
 
@@ -964,7 +964,7 @@ ada_value_of_variable (struct varobj *var, enum varobj_display_formats format)
 /* Implement the "value_is_changeable_p" routine for Ada.  */
 
 static int
-ada_value_is_changeable_p (struct varobj *var)
+ada_value_is_changeable_p (const struct varobj *var)
 {
   struct type *type = var->value ? value_type (var->value) : var->type;
 
@@ -990,7 +990,7 @@ ada_value_is_changeable_p (struct varobj *var)
 /* Implement the "value_has_mutated" routine for Ada.  */
 
 static int
-ada_value_has_mutated (struct varobj *var, struct value *new_val,
+ada_value_has_mutated (const struct varobj *var, struct value *new_val,
 		       struct type *new_type)
 {
   int i;
diff --git a/gdb/c-varobj.c b/gdb/c-varobj.c
index bd0e5fb..c706eb0 100644
--- a/gdb/c-varobj.c
+++ b/gdb/c-varobj.c
@@ -35,7 +35,7 @@ static void cplus_class_num_children (struct type *type, int children[3]);
    thing to do is to compare the child's name with ANONYMOUS_*_NAME.  */
 
 int
-varobj_is_anonymous_child (struct varobj *child)
+varobj_is_anonymous_child (const struct varobj *child)
 {
   return (strcmp (child->name, ANONYMOUS_STRUCT_NAME) == 0
 	  || strcmp (child->name, ANONYMOUS_UNION_NAME) == 0);
@@ -130,7 +130,7 @@ adjust_value_for_child_access (struct value **value,
    a valid path expression?  */
 
 static int
-c_is_path_expr_parent (struct varobj *var)
+c_is_path_expr_parent (const struct varobj *var)
 {
   struct type *type;
 
@@ -179,7 +179,7 @@ c_is_path_expr_parent (struct varobj *var)
 /* C */
 
 static int
-c_number_of_children (struct varobj *var)
+c_number_of_children (const struct varobj *var)
 {
   struct type *type = varobj_get_value_type (var);
   int children = 0;
@@ -230,7 +230,7 @@ c_number_of_children (struct varobj *var)
 }
 
 static char *
-c_name_of_variable (struct varobj *parent)
+c_name_of_variable (const struct varobj *parent)
 {
   return xstrdup (parent->name);
 }
@@ -431,7 +431,7 @@ c_name_of_child (struct varobj *parent, int index)
 }
 
 static char *
-c_path_expr_of_child (struct varobj *child)
+c_path_expr_of_child (const struct varobj *child)
 {
   char *path_expr;
 
@@ -462,7 +462,7 @@ c_type_of_child (struct varobj *parent, int index)
    to return the real type of the variable.  */
 
 static struct type *
-get_type (struct varobj *var)
+get_type (const struct varobj *var)
 {
   struct type *type;
 
@@ -474,7 +474,7 @@ get_type (struct varobj *var)
 }
 
 static char *
-c_value_of_variable (struct varobj *var, enum varobj_display_formats format)
+c_value_of_variable (const struct varobj *var, enum varobj_display_formats format)
 {
   /* BOGUS: if val_print sees a struct/class, or a reference to one,
      it will print out its children instead of "{...}".  So we need to
@@ -558,7 +558,7 @@ enum vsections
 /* C++ */
 
 static int
-cplus_number_of_children (struct varobj *var)
+cplus_number_of_children (const struct varobj *var)
 {
   struct value *value = NULL;
   struct type *type;
@@ -671,7 +671,7 @@ cplus_class_num_children (struct type *type, int children[3])
 }
 
 static char *
-cplus_name_of_variable (struct varobj *parent)
+cplus_name_of_variable (const struct varobj *parent)
 {
   return c_name_of_variable (parent);
 }
@@ -906,7 +906,7 @@ cplus_name_of_child (struct varobj *parent, int index)
 }
 
 static char *
-cplus_path_expr_of_child (struct varobj *child)
+cplus_path_expr_of_child (const struct varobj *child)
 {
   char *path_expr;
 
@@ -934,7 +934,7 @@ cplus_type_of_child (struct varobj *parent, int index)
 }
 
 static char *
-cplus_value_of_variable (struct varobj *var, 
+cplus_value_of_variable (const struct varobj *var,
 			 enum varobj_display_formats format)
 {
 
diff --git a/gdb/jv-varobj.c b/gdb/jv-varobj.c
index 40c1b95..1ad13cd 100644
--- a/gdb/jv-varobj.c
+++ b/gdb/jv-varobj.c
@@ -21,13 +21,13 @@
 /* Java */
 
 static int
-java_number_of_children (struct varobj *var)
+java_number_of_children (const struct varobj *var)
 {
   return cplus_varobj_ops.number_of_children (var);
 }
 
 static char *
-java_name_of_variable (struct varobj *parent)
+java_name_of_variable (const struct varobj *parent)
 {
   char *p, *name;
 
@@ -66,7 +66,7 @@ java_name_of_child (struct varobj *parent, int index)
 }
 
 static char *
-java_path_expr_of_child (struct varobj *child)
+java_path_expr_of_child (const struct varobj *child)
 {
   return NULL;
 }
@@ -84,7 +84,7 @@ java_type_of_child (struct varobj *parent, int index)
 }
 
 static char *
-java_value_of_variable (struct varobj *var, enum varobj_display_formats format)
+java_value_of_variable (const struct varobj *var, enum varobj_display_formats format)
 {
   return cplus_varobj_ops.value_of_variable (var, format);
 }
diff --git a/gdb/varobj.c b/gdb/varobj.c
index 28d388e..0daef91 100644
--- a/gdb/varobj.c
+++ b/gdb/varobj.c
@@ -193,9 +193,9 @@ static int install_new_value (struct varobj *var, struct value *value,
 
 /* Language-specific routines.  */
 
-static int number_of_children (struct varobj *);
+static int number_of_children (const struct varobj *);
 
-static char *name_of_variable (struct varobj *);
+static char *name_of_variable (const struct varobj *);
 
 static char *name_of_child (struct varobj *, int);
 
@@ -206,7 +206,7 @@ static struct value *value_of_child (struct varobj *parent, int index);
 static char *my_value_of_variable (struct varobj *var,
 				   enum varobj_display_formats format);
 
-static int is_root_p (struct varobj *var);
+static int is_root_p (const struct varobj *var);
 
 static struct varobj *varobj_add_child (struct varobj *var,
 					struct varobj_item *item);
@@ -230,7 +230,7 @@ static struct vlist **varobj_table;
 
 /* API Implementation */
 static int
-is_root_p (struct varobj *var)
+is_root_p (const struct varobj *var)
 {
   return (var->root->rootvar == var);
 }
@@ -239,7 +239,7 @@ is_root_p (struct varobj *var)
 /* Helper function to install a Python environment suitable for
    use during operations on VAR.  */
 struct cleanup *
-varobj_ensure_python_env (struct varobj *var)
+varobj_ensure_python_env (const struct varobj *var)
 {
   return ensure_python_env (var->root->exp->gdbarch,
 			    var->root->exp->language_defn);
@@ -487,7 +487,7 @@ varobj_get_handle (char *objname)
 /* Given the handle, return the name of the object.  */
 
 char *
-varobj_get_objname (struct varobj *var)
+varobj_get_objname (const struct varobj *var)
 {
   return var->obj_name;
 }
@@ -496,7 +496,7 @@ varobj_get_objname (struct varobj *var)
    result must be freed by the caller.  */
 
 char *
-varobj_get_expression (struct varobj *var)
+varobj_get_expression (const struct varobj *var)
 {
   return name_of_variable (var);
 }
@@ -600,13 +600,13 @@ varobj_set_display_format (struct varobj *var,
 }
 
 enum varobj_display_formats
-varobj_get_display_format (struct varobj *var)
+varobj_get_display_format (const struct varobj *var)
 {
   return var->format;
 }
 
 char *
-varobj_get_display_hint (struct varobj *var)
+varobj_get_display_hint (const struct varobj *var)
 {
   char *result = NULL;
 
@@ -630,7 +630,7 @@ varobj_get_display_hint (struct varobj *var)
 /* Return true if the varobj has items after TO, false otherwise.  */
 
 int
-varobj_has_more (struct varobj *var, int to)
+varobj_has_more (const struct varobj *var, int to)
 {
   if (VEC_length (varobj_p, var->children) > to)
     return 1;
@@ -643,7 +643,7 @@ varobj_has_more (struct varobj *var, int to)
    inside that thread, returns GDB id of the thread -- which
    is always positive.  Otherwise, returns -1.  */
 int
-varobj_get_thread_id (struct varobj *var)
+varobj_get_thread_id (const struct varobj *var)
 {
   if (var->root->valid_block && var->root->thread_id > 0)
     return var->root->thread_id;
@@ -665,7 +665,7 @@ varobj_set_frozen (struct varobj *var, int frozen)
 }
 
 int
-varobj_get_frozen (struct varobj *var)
+varobj_get_frozen (const struct varobj *var)
 {
   return var->frozen;
 }
@@ -741,7 +741,7 @@ install_dynamic_child (struct varobj *var,
 #if HAVE_PYTHON
 
 static int
-dynamic_varobj_has_child_method (struct varobj *var)
+dynamic_varobj_has_child_method (const struct varobj *var)
 {
   struct cleanup *back_to;
   PyObject *printer = var->dynamic->pretty_printer;
@@ -991,7 +991,7 @@ varobj_get_type (struct varobj *var)
 /* Obtain the type of an object variable.  */
 
 struct type *
-varobj_get_gdb_type (struct varobj *var)
+varobj_get_gdb_type (const struct varobj *var)
 {
   return var->type;
 }
@@ -1000,7 +1000,7 @@ varobj_get_gdb_type (struct varobj *var)
    a valid path expression?  */
 
 static int
-is_path_expr_parent (struct varobj *var)
+is_path_expr_parent (const struct varobj *var)
 {
   gdb_assert (var->root->lang_ops->is_path_expr_parent != NULL);
   return var->root->lang_ops->is_path_expr_parent (var);
@@ -1011,7 +1011,7 @@ is_path_expr_parent (struct varobj *var)
    parent.  */
 
 int
-varobj_default_is_path_expr_parent (struct varobj *var)
+varobj_default_is_path_expr_parent (const struct varobj *var)
 {
   return 1;
 }
@@ -1048,13 +1048,13 @@ varobj_get_path_expr (struct varobj *var)
 }
 
 const struct language_defn *
-varobj_get_language (struct varobj *var)
+varobj_get_language (const struct varobj *var)
 {
   return var->root->exp->language_defn;
 }
 
 int
-varobj_get_attributes (struct varobj *var)
+varobj_get_attributes (const struct varobj *var)
 {
   int attributes = 0;
 
@@ -1068,7 +1068,7 @@ varobj_get_attributes (struct varobj *var)
 /* Return true if VAR is a dynamic varobj.  */
 
 int
-varobj_is_dynamic_p (struct varobj *var)
+varobj_is_dynamic_p (const struct varobj *var)
 {
   return var->dynamic->pretty_printer != NULL;
 }
@@ -1517,7 +1517,7 @@ install_new_value (struct varobj *var, struct value *value, int initial)
    selected sub-range of VAR.  If no range was selected using
    -var-set-update-range, then both will be -1.  */
 void
-varobj_get_child_range (struct varobj *var, int *from, int *to)
+varobj_get_child_range (const struct varobj *var, int *from, int *to)
 {
   *from = var->from;
   *to = var->to;
@@ -1579,7 +1579,7 @@ varobj_set_visualizer (struct varobj *var, const char *visualizer)
    NEW_VALUE may be NULL, if the varobj is now out of scope.  */
 
 static int
-varobj_value_has_mutated (struct varobj *var, struct value *new_value,
+varobj_value_has_mutated (const struct varobj *var, struct value *new_value,
 			  struct type *new_type)
 {
   /* If we haven't previously computed the number of children in var,
@@ -2209,7 +2209,7 @@ make_cleanup_free_variable (struct varobj *var)
 
    For example, top-level references are always stripped.  */
 struct type *
-varobj_get_value_type (struct varobj *var)
+varobj_get_value_type (const struct varobj *var)
 {
   struct type *type;
 
@@ -2278,7 +2278,7 @@ cppop (struct cpstack **pstack)
    is the number of children that the user will see in the variable
    display.  */
 static int
-number_of_children (struct varobj *var)
+number_of_children (const struct varobj *var)
 {
   return (*var->root->lang_ops->number_of_children) (var);
 }
@@ -2286,7 +2286,7 @@ number_of_children (struct varobj *var)
 /* What is the expression for the root varobj VAR? Returns a malloc'd
    string.  */
 static char *
-name_of_variable (struct varobj *var)
+name_of_variable (const struct varobj *var)
 {
   return (*var->root->lang_ops->name_of_variable) (var);
 }
@@ -2303,7 +2303,7 @@ name_of_child (struct varobj *var, int index)
    to it and return 1.  Otherwise, return 0.  */
 
 static int
-check_scope (struct varobj *var)
+check_scope (const struct varobj *var)
 {
   struct frame_info *fi;
   int scope;
@@ -2514,7 +2514,7 @@ varobj_formatted_print_options (struct value_print_options *opts,
 char *
 varobj_value_get_print_value (struct value *value,
 			      enum varobj_display_formats format,
-			      struct varobj *var)
+			      const struct varobj *var)
 {
   struct ui_file *stb;
   struct cleanup *old_chain;
@@ -2645,7 +2645,7 @@ varobj_value_get_print_value (struct value *value,
 }
 
 int
-varobj_editable_p (struct varobj *var)
+varobj_editable_p (const struct varobj *var)
 {
   struct type *type;
 
@@ -2673,7 +2673,7 @@ varobj_editable_p (struct varobj *var)
 /* Call VAR's value_is_changeable_p language-specific callback.  */
 
 int
-varobj_value_is_changeable_p (struct varobj *var)
+varobj_value_is_changeable_p (const struct varobj *var)
 {
   return var->root->lang_ops->value_is_changeable_p (var);
 }
@@ -2682,7 +2682,7 @@ varobj_value_is_changeable_p (struct varobj *var)
    selected frame, and not bound to thread/frame.  Such variable objects
    are created using '@' as frame specifier to -var-create.  */
 int
-varobj_floating_p (struct varobj *var)
+varobj_floating_p (const struct varobj *var)
 {
   return var->root->floating;
 }
@@ -2691,7 +2691,7 @@ varobj_floating_p (struct varobj *var)
    languages.  */
 
 int
-varobj_default_value_is_changeable_p (struct varobj *var)
+varobj_default_value_is_changeable_p (const struct varobj *var)
 {
   int r;
   struct type *type;
diff --git a/gdb/varobj.h b/gdb/varobj.h
index 145b963..8678889 100644
--- a/gdb/varobj.h
+++ b/gdb/varobj.h
@@ -167,11 +167,11 @@ struct varobj
 struct lang_varobj_ops
 {
   /* The number of children of PARENT.  */
-  int (*number_of_children) (struct varobj *parent);
+  int (*number_of_children) (const struct varobj *parent);
 
   /* The name (expression) of a root varobj.  The returned value must be freed
      by the caller.  */
-  char *(*name_of_variable) (struct varobj *parent);
+  char *(*name_of_variable) (const struct varobj *parent);
 
   /* The name of the INDEX'th child of PARENT.  The returned value must be
      freed by the caller.  */
@@ -180,7 +180,7 @@ struct lang_varobj_ops
   /* Returns the rooted expression of CHILD, which is a variable
      obtain that has some parent.  The returned value must be freed by the
      caller.  */
-  char *(*path_expr_of_child) (struct varobj *child);
+  char *(*path_expr_of_child) (const struct varobj *child);
 
   /* The ``struct value *'' of the INDEX'th child of PARENT.  The returned
      value must be freed by the caller.  */
@@ -191,7 +191,7 @@ struct lang_varobj_ops
 
   /* The current value of VAR.  The returned value must be freed by the
      caller.  */
-  char *(*value_of_variable) (struct varobj *var,
+  char *(*value_of_variable) (const struct varobj *var,
 			      enum varobj_display_formats format);
 
   /* Return non-zero if changes in value of VAR must be detected and
@@ -202,7 +202,7 @@ struct lang_varobj_ops
 
      Return value of 0 means that gdb need not call value_fetch_lazy
      for the value of this variable object.  */
-  int (*value_is_changeable_p) (struct varobj *var);
+  int (*value_is_changeable_p) (const struct varobj *var);
 
   /* Return nonzero if the type of VAR has mutated.
 
@@ -216,14 +216,14 @@ struct lang_varobj_ops
      children is set (not < 0).
 
      Languages where types do not mutate can set this to NULL.  */
-  int (*value_has_mutated) (struct varobj *var, struct value *new_value,
+  int (*value_has_mutated) (const struct varobj *var, struct value *new_value,
 			    struct type *new_type);
 
   /* Return nonzero if VAR is a suitable path expression parent.
 
      For C like languages with anonymous structures and unions an anonymous
      structure or union is not a suitable parent.  */
-  int (*is_path_expr_parent) (struct varobj *var);
+  int (*is_path_expr_parent) (const struct varobj *var);
 };
 
 extern const struct lang_varobj_ops c_varobj_ops;
@@ -242,9 +242,9 @@ extern char *varobj_gen_name (void);
 
 extern struct varobj *varobj_get_handle (char *name);
 
-extern char *varobj_get_objname (struct varobj *var);
+extern char *varobj_get_objname (const struct varobj *var);
 
-extern char *varobj_get_expression (struct varobj *var);
+extern char *varobj_get_expression (const struct varobj *var);
 
 extern int varobj_delete (struct varobj *var, char ***dellist,
 			  int only_children);
@@ -254,19 +254,19 @@ extern enum varobj_display_formats varobj_set_display_format (
 					enum varobj_display_formats format);
 
 extern enum varobj_display_formats varobj_get_display_format (
-							struct varobj *var);
+						const struct varobj *var);
 
-extern int varobj_get_thread_id (struct varobj *var);
+extern int varobj_get_thread_id (const struct varobj *var);
 
 extern void varobj_set_frozen (struct varobj *var, int frozen);
 
-extern int varobj_get_frozen (struct varobj *var);
+extern int varobj_get_frozen (const struct varobj *var);
 
-extern void varobj_get_child_range (struct varobj *var, int *from, int *to);
+extern void varobj_get_child_range (const struct varobj *var, int *from, int *to);
 
 extern void varobj_set_child_range (struct varobj *var, int from, int to);
 
-extern char *varobj_get_display_hint (struct varobj *var);
+extern char *varobj_get_display_hint (const struct varobj *var);
 
 extern int varobj_get_num_children (struct varobj *var);
 
@@ -283,13 +283,13 @@ extern VEC (varobj_p)* varobj_list_children (struct varobj *var,
 
 extern char *varobj_get_type (struct varobj *var);
 
-extern struct type *varobj_get_gdb_type (struct varobj *var);
+extern struct type *varobj_get_gdb_type (const struct varobj *var);
 
 extern char *varobj_get_path_expr (struct varobj *var);
 
-extern const struct language_defn *varobj_get_language (struct varobj *var);
+extern const struct language_defn *varobj_get_language (const struct varobj *var);
 
-extern int varobj_get_attributes (struct varobj *var);
+extern int varobj_get_attributes (const struct varobj *var);
 
 extern char *varobj_get_formatted_value (struct varobj *var,
 					 enum varobj_display_formats format);
@@ -306,33 +306,33 @@ extern VEC(varobj_update_result) *varobj_update (struct varobj **varp,
 
 extern void varobj_invalidate (void);
 
-extern int varobj_editable_p (struct varobj *var);
+extern int varobj_editable_p (const struct varobj *var);
 
-extern int varobj_floating_p (struct varobj *var);
+extern int varobj_floating_p (const struct varobj *var);
 
 extern void varobj_set_visualizer (struct varobj *var,
 				   const char *visualizer);
 
 extern void varobj_enable_pretty_printing (void);
 
-extern int varobj_has_more (struct varobj *var, int to);
+extern int varobj_has_more (const struct varobj *var, int to);
 
-extern int varobj_is_dynamic_p (struct varobj *var);
+extern int varobj_is_dynamic_p (const struct varobj *var);
 
-extern struct cleanup *varobj_ensure_python_env (struct varobj *var);
+extern struct cleanup *varobj_ensure_python_env (const struct varobj *var);
 
-extern int varobj_default_value_is_changeable_p (struct varobj *var);
-extern int varobj_value_is_changeable_p (struct varobj *var);
+extern int varobj_default_value_is_changeable_p (const struct varobj *var);
+extern int varobj_value_is_changeable_p (const struct varobj *var);
 
-extern struct type *varobj_get_value_type (struct varobj *var);
+extern struct type *varobj_get_value_type (const struct varobj *var);
 
-extern int varobj_is_anonymous_child (struct varobj *child);
+extern int varobj_is_anonymous_child (const struct varobj *child);
 
 extern struct varobj *varobj_get_path_expr_parent (struct varobj *var);
 
 extern char *varobj_value_get_print_value (struct value *value,
 					   enum varobj_display_formats format,
-					   struct varobj *var);
+					   const struct varobj *var);
 
 extern void varobj_formatted_print_options (struct value_print_options *opts,
 					    enum varobj_display_formats format);
@@ -340,6 +340,6 @@ extern void varobj_formatted_print_options (struct value_print_options *opts,
 extern void varobj_restrict_range (VEC (varobj_p) *children, int *from,
 				   int *to);
 
-extern int varobj_default_is_path_expr_parent (struct varobj *var);
+extern int varobj_default_is_path_expr_parent (const struct varobj *var);
 
 #endif /* VAROBJ_H */
-- 
2.1.4