Rewrite registry.h

This rewrites registry.h, removing all the macros and replacing it
with relatively ordinary template classes.  The result is less code
than the previous setup.  It replaces large macros with a relatively
straightforward C++ class, and now manages its own cleanup.

The existing type-safe "key" class is replaced with the equivalent
template class.  This approach ended up requiring relatively few
changes to the users of the registry code in gdb -- code using the key
system just required a small change to the key's declaration.

All existing users of the old C-like API are now converted to use the
type-safe API.  This mostly involved changing explicit deletion
functions to be an operator() in a deleter class.

The old "save/free" two-phase process is removed, and replaced with a
single "free" phase.  No existing code used both phases.

The old "free" callbacks took a parameter for the enclosing container
object.  However, this wasn't truly needed and is removed here as
well.

1 files changed, 3 insertions, 2 deletions

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 6504081..d49baf9 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -334,7 +334,7 @@ struct ada_inferior_data
 };
 
 /* Our key to this module's inferior data.  */
-static const struct inferior_key<ada_inferior_data> ada_inferior_data;
+static const registry<inferior>::key<ada_inferior_data> ada_inferior_data;
 
 /* Return our inferior data for the given inferior (INF).
 
@@ -376,7 +376,8 @@ struct ada_pspace_data
 };
 
 /* Key to our per-program-space data.  */
-static const struct program_space_key<ada_pspace_data> ada_pspace_data_handle;
+static const registry<program_space>::key<ada_pspace_data>
+  ada_pspace_data_handle;
 
 /* Return this module's data for the given program space (PSPACE).
    If not is found, add a zero'ed one now.