Index: /branches/watchpoints/level-1/l1-error-system.lisp
===================================================================
--- /branches/watchpoints/level-1/l1-error-system.lisp	(revision 12902)
+++ /branches/watchpoints/level-1/l1-error-system.lisp	(revision 12903)
@@ -105,7 +105,8 @@
 (define-condition write-to-watched-object (storage-condition)
   ((address :initarg :address)
+   (instruction :initform nil :initarg :instruction)
    (object :initform nil :initarg :object))
   (:report (lambda (c s)
-	     (with-slots (object address) c
+	     (with-slots (object address instruction) c
 	       (if (uvectorp object)
 		 ;; This is safe only because watched objects are in a
@@ -121,5 +122,12 @@
 			(index (/ offset bytes-per-element)))
 		   (format s "Write to watched object ~s at address #x~x (uvector index ~d)." object address index))
-		 (format s "Write to watched object ~s at address #x~x" object address))))))
+		 (format s "Write to watched object ~s at address #x~x" object address))
+	       (let* ((ds (make-x86-disassembly-state :mode-64 #+x8664-target t
+						      #+x8632-target nil
+                                                      :code-vector nil
+                                                      :code-pointer 0))
+                      (str (with-output-to-string (*standard-output*)
+                             (x86-print-one-disassembled-instruction ds instruction))))
+                 (format s "~&Faulting instruction: ~a" (string-trim " " str)))))))
 
 (define-condition type-error (error)