gdb/

2009-02-06  Jim Blandy  <jimb@codesourcery.com>
	    Daniel Jacobowitz  <dan@codesourcery.com>
	    Vladimir Prus  <vladimir@codesourcery.com>
	    Pedro Alves  <pedro@codesourcery.com>

	* defs.h (enum lval_type): New value: lval_computed.
	* value.h (struct lval_funcs): New type.
	(allocate_computed_value, value_computed_funcs)
	(value_computed_closure): New declarations.
	* value.c (struct value): Add a structure to the location union
	for computed lvalues, containing 'funcs' and 'closure' members.
	(allocate_computed_value, value_computed_funcs)
	(value_computed_closure): New functions.
	(value_free): For computed lvalues, call the closure's
	'free_closure' function before freeing the value itself.
	(value_copy): If we're copying an lval_computed value, call the
	closure's 'copy_closure' function.
	(set_value_component_location): If the original value is a
	computed lvalue, then call the closure's 'copy_closure' function.
	(value_of_internalvar): If an internal variable's value is a
	computed lvalue, make retrieving its value produce an equivalent
	computed lvalue.
	* valops.c (value_fetch_lazy): Unlazy computed lvalues by calling
	their read function.
	(value_assign): Assign to computed lvalues by calling their write
	function.

gdb/doc/
2009-02-06  Pedro Alves  <pedro@codesourcery.com>

	* gdbint.texinfo (Values): New chapter.

gdb/defs.h

@@ -652,7 +652,10 @@ enum lval_type
     /* In a gdb internal variable.  */
     lval_internalvar,
     /* Part of a gdb internal variable (structure field).  */
-    lval_internalvar_component
+    lval_internalvar_component,
+    /* Value's bits are fetched and stored using functions provided by
+       its creator.  */
+    lval_computed
   };
 
 /* Control types for commands */