Vladimir Marangozov's long-awaited malloc restructuring.
For more comments, read the patches@python.org archives.
For documentation read the comments in mymalloc.h and objimpl.h.

(This is not exactly what Vladimir posted to the patches list; I've
made a few changes, and Vladimir sent me a fix in private email for a
problem that only occurs in debug mode.  I'm also holding back on his
change to main.c, which seems unnecessary to me.)
diff --git a/Modules/dbmmodule.c b/Modules/dbmmodule.c
index 501c3f4..d4fc1bf 100644
--- a/Modules/dbmmodule.c
+++ b/Modules/dbmmodule.c
@@ -62,7 +62,7 @@
 {
         dbmobject *dp;
 
-	dp = PyObject_NEW(dbmobject, &Dbmtype);
+	dp = PyObject_New(dbmobject, &Dbmtype);
 	if (dp == NULL)
 		return NULL;
 	dp->di_size = -1;
@@ -82,7 +82,7 @@
 {
         if ( dp->di_dbm )
 		dbm_close(dp->di_dbm);
-	PyMem_DEL(dp);
+	PyObject_Del(dp);
 }
 
 static int