+
+;;; unique ID for the next object created (to let us track object
+;;; identity even across GC, useful for understanding weird compiler
+;;; bugs where something is supposed to be unique but is instead
+;;; exists as duplicate objects)
+#!+sb-show
+(progn
+ (defvar *object-id-counter* 0)
+ (defun new-object-id ()
+ (prog1
+ *object-id-counter*
+ (incf *object-id-counter*))))