value: Make accessor methods' parameters const-correct

I did a quick pass over value.c and value.h and made some of the accessor methods'
pass-by-reference parameters const-correct. Besides the obvious benefits, this is
required if we want to use them on values that are already declared as const
(such as the parameters to lval_funcs).

There's probably a lot more stuff that can be made const, here and elsewhere.

gdb/ChangeLog:
2016-04-08  Martin Galvan  <martin.galvan@tallertechnologies.com>

    * value.c (value_next): Make pass-by-reference parameters const-correct.
    (value_parent): Likewise.
    (value_enclosing_type): Likewise.
    (value_lazy): Likewise.
    (value_stack): Likewise.
    (value_embedded_offset): Likewise.
    (value_pointed_to_offset): Likewise.
    (value_raw_address): Likewise.
    (deprecated_value_modifiable): Likewise.
    (value_free_to_mark): Likewise.
    (value_release_to_mark): Likewise.
    (internalvar_name): Likewise.
    (readjust_indirect_value_type): Likewise.
    (value_initialized): Likewise.
    * value.h (value_next): Likewise.
    (value_parent): Likewise.
    (value_enclosing_type): Likewise.
    (value_lazy): Likewise.
    (value_stack): Likewise.
    (value_embedded_offset): Likewise.
    (value_pointed_to_offset): Likewise.
    (value_raw_address): Likewise.
    (deprecated_value_modifiable): Likewise.
    (value_free_to_mark): Likewise.
    (value_release_to_mark): Likewise.
    (internalvar_name): Likewise.
    (readjust_indirect_value_type): Likewise.
    (value_initialized): Likewise.

3 files changed, 61 insertions, 30 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index dfd49b9..87f7679 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,34 @@
+2016-04-08  Martin Galvan  <martin.galvan@tallertechnologies.com>
+
+	* value.c (value_next): Make pass-by-reference parameters const-correct.
+	(value_parent): Likewise.
+	(value_enclosing_type): Likewise.
+	(value_lazy): Likewise.
+	(value_stack): Likewise.
+	(value_embedded_offset): Likewise.
+	(value_pointed_to_offset): Likewise.
+	(value_raw_address): Likewise.
+	(deprecated_value_modifiable): Likewise.
+	(value_free_to_mark): Likewise.
+	(value_release_to_mark): Likewise.
+	(internalvar_name): Likewise.
+	(readjust_indirect_value_type): Likewise.
+	(value_initialized): Likewise.
+	* value.h (value_next): Likewise.
+	(value_parent): Likewise.
+	(value_enclosing_type): Likewise.
+	(value_lazy): Likewise.
+	(value_stack): Likewise.
+	(value_embedded_offset): Likewise.
+	(value_pointed_to_offset): Likewise.
+	(value_raw_address): Likewise.
+	(deprecated_value_modifiable): Likewise.
+	(value_free_to_mark): Likewise.
+	(value_release_to_mark): Likewise.
+	(internalvar_name): Likewise.
+	(readjust_indirect_value_type): Likewise.
+	(value_initialized): Likewise.
+
 2016-04-07  Yao Qi  <yao.qi@linaro.org>
 
 	* record-full.c (record_full_insert_breakpoint): Return
diff --git a/gdb/value.c b/gdb/value.c
index 3b66946..5aeed02 100644
--- a/gdb/value.c
+++ b/gdb/value.c
@@ -1093,7 +1093,7 @@ allocate_optimized_out_value (struct type *type)
 /* Accessor methods.  */
 
 struct value *
-value_next (struct value *value)
+value_next (const struct value *value)
 {
   return value->next;
 }
@@ -1143,7 +1143,7 @@ set_value_bitsize (struct value *value, int bit)
 }
 
 struct value *
-value_parent (struct value *value)
+value_parent (const struct value *value)
 {
   return value->parent;
 }
@@ -1179,7 +1179,7 @@ value_contents_all_raw (struct value *value)
 }
 
 struct type *
-value_enclosing_type (struct value *value)
+value_enclosing_type (const struct value *value)
 {
   return value->enclosing_type;
 }
@@ -1388,7 +1388,7 @@ value_contents_copy (struct value *dst, int dst_offset,
 }
 
 int
-value_lazy (struct value *value)
+value_lazy (const struct value *value)
 {
   return value->lazy;
 }
@@ -1400,7 +1400,7 @@ set_value_lazy (struct value *value, int val)
 }
 
 int
-value_stack (struct value *value)
+value_stack (const struct value *value)
 {
   return value->stack;
 }
@@ -1481,7 +1481,7 @@ value_bits_synthetic_pointer (const struct value *value,
 }
 
 int
-value_embedded_offset (struct value *value)
+value_embedded_offset (const struct value *value)
 {
   return value->embedded_offset;
 }
@@ -1493,7 +1493,7 @@ set_value_embedded_offset (struct value *value, int val)
 }
 
 int
-value_pointed_to_offset (struct value *value)
+value_pointed_to_offset (const struct value *value)
 {
   return value->pointed_to_offset;
 }
@@ -1546,7 +1546,7 @@ value_address (const struct value *value)
 }
 
 CORE_ADDR
-value_raw_address (struct value *value)
+value_raw_address (const struct value *value)
 {
   if (value->lval == lval_internalvar
       || value->lval == lval_internalvar_component
@@ -1583,7 +1583,7 @@ deprecated_value_regnum_hack (struct value *value)
 }
 
 int
-deprecated_value_modifiable (struct value *value)
+deprecated_value_modifiable (const struct value *value)
 {
   return value->modifiable;
 }
@@ -1644,7 +1644,7 @@ value_free (struct value *val)
 /* Free all values allocated since MARK was obtained by value_mark
    (except for those released).  */
 void
-value_free_to_mark (struct value *mark)
+value_free_to_mark (const struct value *mark)
 {
   struct value *val;
   struct value *next;
@@ -1736,7 +1736,7 @@ release_value_or_incref (struct value *val)
 
 /* Release all values up to mark  */
 struct value *
-value_release_to_mark (struct value *mark)
+value_release_to_mark (const struct value *mark)
 {
   struct value *val;
   struct value *next;
@@ -2500,7 +2500,7 @@ clear_internalvar (struct internalvar *var)
 }
 
 char *
-internalvar_name (struct internalvar *var)
+internalvar_name (const struct internalvar *var)
 {
   return var->name;
 }
@@ -3772,8 +3772,8 @@ coerce_ref_if_computed (const struct value *arg)
 
 struct value *
 readjust_indirect_value_type (struct value *value, struct type *enc_type,
-			      struct type *original_type,
-			      struct value *original_value)
+			      const struct type *original_type,
+			      const struct value *original_value)
 {
   /* Re-adjust type.  */
   deprecated_set_value_type (value, TYPE_TARGET_TYPE (original_type));
@@ -3878,7 +3878,7 @@ set_value_initialized (struct value *val, int status)
 /* Return the initialized field in a value struct.  */
 
 int
-value_initialized (struct value *val)
+value_initialized (const struct value *val)
 {
   return val->initialized;
 }
diff --git a/gdb/value.h b/gdb/value.h
index 2eac5ef..f8ec854 100644
--- a/gdb/value.h
+++ b/gdb/value.h
@@ -93,7 +93,7 @@ struct value;
    put into the value history or exposed to Python are taken off this
    list.  */
 
-struct value *value_next (struct value *);
+struct value *value_next (const struct value *);
 
 /* Type of the value.  */
 
@@ -126,7 +126,7 @@ extern void set_value_bitpos (struct value *, int bit);
    single read from the target when displaying multiple
    bitfields.  */
 
-struct value *value_parent (struct value *);
+struct value *value_parent (const struct value *);
 extern void set_value_parent (struct value *value, struct value *parent);
 
 /* Describes offset of a value within lval of a structure in bytes.
@@ -142,7 +142,7 @@ extern void set_value_offset (struct value *, int offset);
    relevant if lval != not_lval.''.  Shouldn't the value instead be
    not_lval and be done with it?  */
 
-extern int deprecated_value_modifiable (struct value *value);
+extern int deprecated_value_modifiable (const struct value *value);
 
 /* If a value represents a C++ object, then the `type' field gives the
    object's compile-time type.  If the object actually belongs to some
@@ -185,7 +185,7 @@ extern int deprecated_value_modifiable (struct value *value);
    `type', and `embedded_offset' is zero, so everything works
    normally.  */
 
-extern struct type *value_enclosing_type (struct value *);
+extern struct type *value_enclosing_type (const struct value *);
 extern void set_value_enclosing_type (struct value *val,
 				      struct type *new_type);
 
@@ -205,9 +205,9 @@ extern struct type *value_actual_type (struct value *value,
 				       int resolve_simple_types,
 				       int *real_type_found);
 
-extern int value_pointed_to_offset (struct value *value);
+extern int value_pointed_to_offset (const struct value *value);
 extern void set_value_pointed_to_offset (struct value *value, int val);
-extern int value_embedded_offset (struct value *value);
+extern int value_embedded_offset (const struct value *value);
 extern void set_value_embedded_offset (struct value *value, int val);
 
 /* For lval_computed values, this structure holds functions used to
@@ -312,10 +312,10 @@ extern void *value_computed_closure (const struct value *value);
    element.  If you ever change the way lazy flag is set and reset, be
    sure to consider this use as well!  */
 
-extern int value_lazy (struct value *);
+extern int value_lazy (const struct value *);
 extern void set_value_lazy (struct value *value, int val);
 
-extern int value_stack (struct value *);
+extern int value_stack (const struct value *);
 extern void set_value_stack (struct value *value, int val);
 
 /* Throw an error complaining that the value has been optimized
@@ -398,7 +398,7 @@ extern void mark_value_bits_optimized_out (struct value *value,
 /* Set or return field indicating whether a variable is initialized or
    not, based on debugging information supplied by the compiler.
    1 = initialized; 0 = uninitialized.  */
-extern int value_initialized (struct value *);
+extern int value_initialized (const struct value *);
 extern void set_value_initialized (struct value *, int);
 
 /* Set COMPONENT's location as appropriate for a component of WHOLE
@@ -425,7 +425,7 @@ extern CORE_ADDR value_address (const struct value *);
 
 /* Like value_address, except the result does not include value's
    offset.  */
-extern CORE_ADDR value_raw_address (struct value *);
+extern CORE_ADDR value_raw_address (const struct value *);
 
 /* Set the address of a value.  */
 extern void set_value_address (struct value *, CORE_ADDR);
@@ -458,8 +458,8 @@ extern struct value *coerce_ref_if_computed (const struct value *arg);
 
 extern struct value * readjust_indirect_value_type (struct value *value,
 						    struct type *enc_type,
-						    struct type *original_type,
-						    struct value *original_val);
+						    const struct type *original_type,
+						    const struct value *original_val);
 
 /* Convert a REF to the object referenced.  */
 
@@ -694,7 +694,7 @@ extern struct value *allocate_repeat_value (struct type *type, int count);
 
 extern struct value *value_mark (void);
 
-extern void value_free_to_mark (struct value *mark);
+extern void value_free_to_mark (const struct value *mark);
 
 extern struct value *value_cstring (const char *ptr, ssize_t len,
 				    struct type *char_type);
@@ -1006,7 +1006,7 @@ extern void value_print_array_elements (struct value *val,
 					struct ui_file *stream, int format,
 					enum val_prettyformat pretty);
 
-extern struct value *value_release_to_mark (struct value *mark);
+extern struct value *value_release_to_mark (const struct value *mark);
 
 extern void val_print (struct type *type, const gdb_byte *valaddr,
 		       int embedded_offset, CORE_ADDR address,
@@ -1034,7 +1034,7 @@ extern void print_variable_and_value (const char *name,
 extern void typedef_print (struct type *type, struct symbol *news,
 			   struct ui_file *stream);
 
-extern char *internalvar_name (struct internalvar *var);
+extern char *internalvar_name (const struct internalvar *var);
 
 extern void preserve_values (struct objfile *);