1.0.29.38: better DESCRIBE
[sbcl.git] / src / code / condition.lisp
index 705d945..0e87f35 100644 (file)
                               ',(all-writers)
                               (sb!c:source-location)))))))
 \f
-;;;; DESCRIBE on CONDITIONs
-
-;;; a function to be used as the guts of DESCRIBE-OBJECT (CONDITION T)
-;;; eventually (once we get CLOS up and running so that we can define
-;;; methods)
-(defun describe-condition (condition stream)
-  (format stream
-          "~&~@<~S ~_is a ~S. ~_Its slot values are ~_~S.~:>~%"
-          condition
-          (type-of condition)
-          (concatenate 'list
-                       (condition-actual-initargs condition)
-                       (condition-assigned-slots condition))))
-\f
 ;;;; various CONDITIONs specified by ANSI
 
 (define-condition serious-condition (condition) ())
 
 (define-condition simple-error (simple-condition error) ())
 
-;;; not specified by ANSI, but too useful not to have around.
-(define-condition simple-style-warning (simple-condition style-warning) ())
-
 (define-condition storage-condition (serious-condition) ())
 
 (define-condition type-error (error)
              (type-error-datum condition)
              (type-error-expected-type condition)))))
 
+;;; not specified by ANSI, but too useful not to have around.
+(define-condition simple-style-warning (simple-condition style-warning) ())
 (define-condition simple-type-error (simple-condition type-error) ())
 
 (define-condition program-error (error) ())
              "end of file on ~S"
              (stream-error-stream condition)))))
 
+(define-condition closed-stream-error (stream-error) ()
+  (:report
+   (lambda (condition stream)
+     (format stream "~S is closed" (stream-error-stream condition)))))
+
 (define-condition file-error (error)
   ((pathname :reader file-error-pathname :initarg :pathname))
   (:report
            (*print-array* nil))
        (format stream "~S cannot be printed readably." obj)))))
 
-(define-condition reader-error (parse-error stream-error)
-  ((format-control
-    :reader reader-error-format-control
-    :initarg :format-control)
-   (format-arguments
-    :reader reader-error-format-arguments
-    :initarg :format-arguments
-    :initform '()))
-  (:report
-   (lambda (condition stream)
-     (let* ((error-stream (stream-error-stream condition))
-            (pos (file-position-or-nil-for-error error-stream)))
-       (let (lineno colno)
-         (when (and pos
-                    (< pos sb!xc:array-dimension-limit)
-                    ;; KLUDGE: lseek() (which is what FILE-POSITION
-                    ;; reduces to on file-streams) is undefined on
-                    ;; "some devices", which in practice means that it
-                    ;; can claim to succeed on /dev/stdin on Darwin
-                    ;; and Solaris.  This is obviously bad news,
-                    ;; because the READ-SEQUENCE below will then
-                    ;; block, not complete, and the report will never
-                    ;; be printed.  As a workaround, we exclude
-                    ;; interactive streams from this attempt to report
-                    ;; positions.  -- CSR, 2003-08-21
-                    (not (interactive-stream-p error-stream))
-                    (file-position error-stream :start))
-           (let ((string
-                  (make-string pos
-                               :element-type (stream-element-type
-                                              error-stream))))
-             (when (= pos (read-sequence string error-stream))
-               (setq lineno (1+ (count #\Newline string))
-                     colno (- pos
-                              (or (position #\Newline string :from-end t) -1)
-                              1))))
-           (file-position-or-nil-for-error error-stream pos))
-         (format stream
-                 "READER-ERROR ~@[at ~W ~]~
-                  ~@[(line ~W~]~@[, column ~W) ~]~
-                  on ~S:~%~?"
-                 pos lineno colno error-stream
-                 (reader-error-format-control condition)
-                 (reader-error-format-arguments condition)))))))
+(define-condition reader-error (parse-error stream-error) ()
+  (:report (lambda (condition stream)
+             (%report-reader-error condition stream))))
+
+;;; a READER-ERROR whose REPORTing is controlled by FORMAT-CONTROL and
+;;; FORMAT-ARGS (the usual case for READER-ERRORs signalled from
+;;; within SBCL itself)
+;;;
+;;; (Inheriting CL:SIMPLE-CONDITION here isn't quite consistent with
+;;; the letter of the ANSI spec: this is not a condition signalled by
+;;; SIGNAL when a format-control is supplied by the function's first
+;;; argument. It seems to me (WHN) to be basically in the spirit of
+;;; the spec, but if not, it'd be straightforward to do our own
+;;; DEFINE-CONDITION SB-INT:SIMPLISTIC-CONDITION with
+;;; FORMAT-CONTROL and FORMAT-ARGS slots, and use that condition in
+;;; place of CL:SIMPLE-CONDITION here.)
+(define-condition simple-reader-error (reader-error simple-condition)
+  ()
+  (:report (lambda (condition stream)
+             (%report-reader-error condition stream :simple t))))
+
+;;; base REPORTing of a READER-ERROR
+;;;
+;;; When SIMPLE, we expect and use SIMPLE-CONDITION-ish FORMAT-CONTROL
+;;; and FORMAT-ARGS slots.
+(defun %report-reader-error (condition stream &key simple)
+  (let* ((error-stream (stream-error-stream condition))
+         (pos (file-position-or-nil-for-error error-stream)))
+    (let (lineno colno)
+      (when (and pos
+                 (< pos sb!xc:array-dimension-limit)
+                 ;; KLUDGE: lseek() (which is what FILE-POSITION
+                 ;; reduces to on file-streams) is undefined on
+                 ;; "some devices", which in practice means that it
+                 ;; can claim to succeed on /dev/stdin on Darwin
+                 ;; and Solaris.  This is obviously bad news,
+                 ;; because the READ-SEQUENCE below will then
+                 ;; block, not complete, and the report will never
+                 ;; be printed.  As a workaround, we exclude
+                 ;; interactive streams from this attempt to report
+                 ;; positions.  -- CSR, 2003-08-21
+                 (not (interactive-stream-p error-stream))
+                 (file-position error-stream :start))
+        (let ((string
+               (make-string pos
+                            :element-type (stream-element-type
+                                           error-stream))))
+          (when (= pos (read-sequence string error-stream))
+            (setq lineno (1+ (count #\Newline string))
+                  colno (- pos
+                           (or (position #\Newline string :from-end t) -1)
+                           1))))
+        (file-position-or-nil-for-error error-stream pos))
+      (pprint-logical-block (stream nil)
+        (format stream
+                "~S ~@[at ~W ~]~
+                    ~@[(line ~W~]~@[, column ~W) ~]~
+                    on ~S"
+                (class-name (class-of condition))
+                pos lineno colno error-stream)
+        (when simple
+          (format stream ":~2I~_~?"
+                  (simple-condition-format-control condition)
+                  (simple-condition-format-arguments condition)))))))
 \f
 ;;;; special SBCL extension conditions
 
               <http://sbcl.sourceforge.net/>.~:@>"
              '((fmakunbound 'compile))))))
 
-(define-condition simple-storage-condition (storage-condition simple-condition) ())
+(define-condition simple-storage-condition (storage-condition simple-condition)
+  ())
 
 ;;; a condition for use in stubs for operations which aren't supported
 ;;; on some platforms
 ;;; unimplemented and (2) unintentionally just screwed up somehow.
 ;;; (Before this condition was defined, test code tried to deal with
 ;;; this by checking for FBOUNDP, but that didn't work reliably. In
-;;; sbcl-0.7.0, a a package screwup left the definition of
+;;; sbcl-0.7.0, a package screwup left the definition of
 ;;; LOAD-FOREIGN in the wrong package, so it was unFBOUNDP even on
 ;;; architectures where it was supposed to be supported, and the
 ;;; regression tests cheerfully passed because they assumed that
 ;;; unFBOUNDPness meant they were running on an system which didn't
 ;;; support the extension.)
 (define-condition unsupported-operator (simple-error) ())
-
 \f
 ;;; (:ansi-cl :function remove)
 ;;; (:ansi-cl :section (a b c))
           (unless (null (cdr rs))
             (terpri s)))))))
 
+(define-condition simple-reference-error (reference-condition simple-error)
+  ())
+
+(define-condition simple-reference-warning (reference-condition simple-warning)
+  ())
+
 (define-condition duplicate-definition (reference-condition warning)
   ((name :initarg :name :reader duplicate-definition-name))
   (:report (lambda (c s)
                    '(:ansi-cl :function make-array)
                    '(:ansi-cl :function sb!xc:upgraded-array-element-type))))
 
-(define-condition displaced-to-array-too-small-error
-    (reference-condition simple-error)
-  ()
-  (:default-initargs
-      :references (list '(:ansi-cl :function adjust-array))))
-
 (define-condition type-warning (reference-condition simple-warning)
   ()
   (:default-initargs :references (list '(:sbcl :node "Handling of Types"))))
     (format-args-mismatch simple-style-warning)
   ())
 
+(define-condition implicit-generic-function-warning (style-warning)
+  ((name :initarg :name :reader implicit-generic-function-name))
+  (:report
+   (lambda (condition stream)
+     (format stream "~@<Implicitly creating new generic function ~S.~:@>"
+             (implicit-generic-function-name condition)))))
+
 (define-condition extension-failure (reference-condition simple-error)
   ())
 
@@ -1064,6 +1081,36 @@ SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
                     "No traps are enabled? How can this be?"
                     stream))))))
 
+(define-condition invalid-array-index-error (type-error)
+  ((array :initarg :array :reader invalid-array-index-error-array)
+   (axis :initarg :axis :reader invalid-array-index-error-axis))
+  (:report
+   (lambda (condition stream)
+     (let ((array (invalid-array-index-error-array condition)))
+       (format stream "Index ~W out of bounds for ~@[axis ~W of ~]~S, ~
+                       should be nonnegative and <~W."
+               (type-error-datum condition)
+               (when (> (array-rank array) 1)
+                 (invalid-array-index-error-axis condition))
+               (type-of array)
+               ;; Extract the bound from (INTEGER 0 (BOUND))
+               (caaddr (type-error-expected-type condition)))))))
+
+(define-condition invalid-array-error (reference-condition type-error) ()
+  (:report
+   (lambda (condition stream)
+     (let ((*print-array* nil))
+       (format stream
+               "~@<Displaced array originally of type ~S has been invalidated ~
+                due its displaced-to array ~S having become too small to hold ~
+                it: the displaced array's dimensions have all been set to zero ~
+                to trap accesses to it.~:@>"
+               (type-error-expected-type condition)
+               (array-displacement (type-error-datum condition))))))
+  (:default-initargs
+      :references
+      (list '(:ansi-cl :function adjust-array))))
+
 (define-condition index-too-large-error (type-error)
   ()
   (:report
@@ -1109,16 +1156,6 @@ SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
                         '(:ansi-cl :section (15 1 2 1))
                         '(:ansi-cl :section (15 1 2 2)))))
 
-(define-condition io-timeout (stream-error)
-  ((direction :reader io-timeout-direction :initarg :direction))
-  (:report
-   (lambda (condition stream)
-     (declare (type stream stream))
-     (format stream
-             "I/O timeout ~(~A~)ing ~S"
-             (io-timeout-direction condition)
-             (stream-error-stream condition)))))
-
 (define-condition namestring-parse-error (parse-error)
   ((complaint :reader namestring-parse-error-complaint :initarg :complaint)
    (args :reader namestring-parse-error-args :initarg :args :initform nil)
@@ -1135,7 +1172,7 @@ SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
 
 (define-condition simple-package-error (simple-condition package-error) ())
 
-(define-condition reader-package-error (reader-error) ())
+(define-condition simple-reader-package-error (simple-reader-error) ())
 
 (define-condition reader-eof-error (end-of-file)
   ((context :reader reader-eof-error-context :initarg :context))
@@ -1146,18 +1183,46 @@ SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
              (stream-error-stream condition)
              (reader-eof-error-context condition)))))
 
-(define-condition reader-impossible-number-error (reader-error)
+(define-condition reader-impossible-number-error (simple-reader-error)
   ((error :reader reader-impossible-number-error-error :initarg :error))
   (:report
    (lambda (condition stream)
      (let ((error-stream (stream-error-stream condition)))
-       (format stream "READER-ERROR ~@[at ~W ~]on ~S:~%~?~%Original error: ~A"
+       (format stream
+               "READER-ERROR ~@[at ~W ~]on ~S:~%~?~%Original error: ~A"
                (file-position-or-nil-for-error error-stream) error-stream
-               (reader-error-format-control condition)
-               (reader-error-format-arguments condition)
+               (simple-condition-format-control condition)
+               (simple-condition-format-arguments condition)
                (reader-impossible-number-error-error condition))))))
 
-(define-condition timeout (serious-condition) ())
+(define-condition standard-readtable-modified-error (reference-condition error)
+  ((operation :initarg :operation :reader standard-readtable-modified-operation))
+  (:report (lambda (condition stream)
+             (format stream "~S would modify the standard readtable."
+                     (standard-readtable-modified-operation condition))))
+  (:default-initargs :references `((:ansi-cl :section (2 1 1 2))
+                                   (:ansi-cl :glossary "standard readtable"))))
+
+(define-condition timeout (serious-condition)
+  ((seconds :initarg :seconds :initform nil :reader timeout-seconds))
+  (:report (lambda (condition stream)
+             (format stream "Timeout occurred~@[ after ~A seconds~]."
+                     (timeout-seconds condition)))))
+
+(define-condition io-timeout (stream-error timeout)
+  ((direction :reader io-timeout-direction :initarg :direction))
+  (:report
+   (lambda (condition stream)
+     (declare (type stream stream))
+     (format stream
+             "I/O timeout ~(~A~)ing ~S."
+             (io-timeout-direction condition)
+             (stream-error-stream condition)))))
+
+(define-condition deadline-timeout (timeout) ()
+  (:report (lambda (condition stream)
+             (format stream "A deadline was reached after ~A seconds."
+                     (timeout-seconds condition)))))
 
 (define-condition declaration-type-conflict-error (reference-condition
                                                    simple-error)
@@ -1170,6 +1235,7 @@ SB-EXT:PACKAGE-LOCKED-ERROR-SYMBOL."))
 
 (define-condition step-condition ()
   ((form :initarg :form :reader step-condition-form))
+
   #!+sb-doc
   (:documentation "Common base class of single-stepping conditions.
 STEP-CONDITION-FORM holds a string representation of the form being
@@ -1180,8 +1246,18 @@ stepped."))
       "Form associated with the STEP-CONDITION.")
 
 (define-condition step-form-condition (step-condition)
-  ((source-path :initarg :source-path :reader step-condition-source-path)
-   (pathname :initarg :pathname :reader step-condition-pathname))
+  ((args :initarg :args :reader step-condition-args))
+  (:report
+   (lambda (condition stream)
+     (let ((*print-circle* t)
+           (*print-pretty* t)
+           (*print-readably* nil))
+       (format stream
+                 "Evaluating call:~%~<  ~@;~A~:>~%~
+                  ~:[With arguments:~%~{  ~S~%~}~;With unknown arguments~]~%"
+               (list (step-condition-form condition))
+               (eq (step-condition-args condition) :unknown)
+               (step-condition-args condition)))))
   #!+sb-doc
   (:documentation "Condition signalled by code compiled with
 single-stepping information when about to execute a form.
@@ -1191,14 +1267,6 @@ holds the source-path to the original form within that file or NIL.
 Associated with this condition are always the restarts STEP-INTO,
 STEP-NEXT, and STEP-CONTINUE."))
 
-#!+sb-doc
-(setf (fdocumentation 'step-condition-source-path 'function)
-      "Source-path of the original form associated with the
-STEP-FORM-CONDITION or NIL."
-      (fdocumentation 'step-condition-pathname 'function)
-      "Pathname of the original source-file associated with the
-STEP-FORM-CONDITION or NIL.")
-
 (define-condition step-result-condition (step-condition)
   ((result :initarg :result :reader step-condition-result)))
 
@@ -1215,14 +1283,316 @@ single-stepping information after executing a form.
 STEP-CONDITION-FORM holds the form, and STEP-CONDITION-RESULT holds
 the values returned by the form as a list. No associated restarts."))
 
-(define-condition step-variable-condition (step-result-condition)
+(define-condition step-finished-condition (step-condition)
   ()
+  (:report
+   (lambda (condition stream)
+     (declare (ignore condition))
+     (format stream "Returning from STEP")))
   #!+sb-doc
-  (:documentation "Condition signalled by code compiled with
-single-stepping information when referencing a variable.
-STEP-CONDITION-FORM hold the symbol, and STEP-CONDITION-RESULT holds
-the value of the variable. No associated restarts."))
+  (:documentation "Condition signaled when STEP returns."))
+\f
+;;; A knob for muffling warnings, mostly for use while loading files.
+(defvar *muffled-warnings* 'uninteresting-redefinition
+  "A type that ought to specify a subtype of WARNING.  Whenever a
+warning is signaled, if the warning if of this type and is not
+handled by any other handler, it will be muffled.")
+\f
+;;; Various STYLE-WARNING signaled in the system.
+;; For the moment, we're only getting into the details for function
+;; redefinitions, but other redefinitions could be done later
+;; (e.g. methods).
+(define-condition redefinition-warning (style-warning)
+  ())
 
+(define-condition function-redefinition-warning (redefinition-warning)
+  ((name :initarg :name :reader function-redefinition-warning-name)
+   (old :initarg :old :reader function-redefinition-warning-old-fdefinition)
+   ;; For DEFGENERIC and perhaps others, the redefinition
+   ;; destructively modifies the original, rather than storing a new
+   ;; object, so there's no NEW here, but only in subclasses.
+   ))
+
+(define-condition redefinition-with-defun (function-redefinition-warning)
+  ((new :initarg :new :reader redefinition-with-defun-new-fdefinition)
+   ;; KLUDGE: it would be nice to fix the unreasonably late
+   ;; back-patching of DEBUG-SOURCEs in the DEBUG-INFO during
+   ;; fasloading and just use the new fdefinition, but for the moment
+   ;; we'll compare the SOURCE-LOCATION created during DEFUN with the
+   ;; previous DEBUG-SOURCE.
+   (new-location :initarg :new-location
+              :reader redefinition-with-defun-new-location))
+  (:report (lambda (warning stream)
+             (format stream "redefining ~S in DEFUN"
+                     (function-redefinition-warning-name warning)))))
+
+(define-condition redefinition-with-defgeneric (function-redefinition-warning)
+  ((new-location :initarg :new-location
+                 :reader redefinition-with-defgeneric-new-location))
+  (:report (lambda (warning stream)
+             (format stream "redefining ~S in DEFGENERIC"
+                     (function-redefinition-warning-name warning)))))
+
+(define-condition redefinition-with-defmethod (redefinition-warning)
+  ((gf :initarg :generic-function
+       :reader redefinition-with-defmethod-generic-function)
+   (qualifiers :initarg :qualifiers
+               :reader redefinition-with-defmethod-qualifiers)
+   (specializers :initarg :specializers
+                 :reader redefinition-with-defmethod-specializers)
+   (new-location :initarg :new-location
+                 :reader redefinition-with-defmethod-new-location)
+   (old-method :initarg :old-method
+               :reader redefinition-with-defmethod-old-method))
+  (:report (lambda (warning stream)
+             (format stream "redefining ~S~{ ~S~} ~S in DEFMETHOD"
+                     (redefinition-with-defmethod-generic-function warning)
+                     (redefinition-with-defmethod-qualifiers warning)
+                     (redefinition-with-defmethod-specializers warning)))))
+
+;; FIXME: see the FIXMEs in defmacro.lisp, then maybe instantiate this.
+(define-condition redefinition-with-defmacro (function-redefinition-warning)
+  ())
+
+;; Here are a few predicates for what people might find interesting
+;; about redefinitions.
+
+;; DEFUN can replace a generic function with an ordinary function.
+;; (Attempting to replace an ordinary function with a generic one
+;; causes an error, though.)
+(defun redefinition-replaces-generic-function-p (warning)
+  (and (typep warning 'redefinition-with-defun)
+       (typep (function-redefinition-warning-old-fdefinition warning)
+              'generic-function)))
+
+(defun redefinition-replaces-compiled-function-with-interpreted-p (warning)
+  (and (typep warning 'redefinition-with-defun)
+       (compiled-function-p
+        (function-redefinition-warning-old-fdefinition warning))
+       (not (compiled-function-p
+             (redefinition-with-defun-new-fdefinition warning)))))
+
+;; Most people seem to agree that re-running a DEFUN in a file is
+;; completely uninteresting.
+(defun uninteresting-ordinary-function-redefinition-p (warning)
+  ;; OAOO violation: this duplicates code in SB-INTROSPECT.
+  ;; Additionally, there are some functions that aren't
+  ;; funcallable-instances for which finding the source location is
+  ;; complicated (e.g. DEFSTRUCT-defined predicates and accessors),
+  ;; but I don't think they're defined with %DEFUN, so the warning
+  ;; isn't raised.
+  (flet ((fdefinition-file-namestring (fdefn)
+           #!+sb-eval
+           (when (typep fdefn 'sb!eval:interpreted-function)
+             (return-from fdefinition-file-namestring
+               (sb!c:definition-source-location-namestring
+                   (sb!eval:interpreted-function-source-location fdefn))))
+           ;; All the following accesses are guarded with conditionals
+           ;; because it's not clear whether any of the slots we're
+           ;; chasing down are guaranteed to be filled in.
+           (let* ((fdefn
+                   ;; KLUDGE: although this looks like it only works
+                   ;; for %SIMPLE-FUNs, in fact there's a pun such
+                   ;; that %SIMPLE-FUN-SELF returns the simple-fun
+                   ;; object for closures and
+                   ;; funcallable-instances. -- CSR, circa 2005
+                   (sb!kernel:%simple-fun-self fdefn))
+                  (code (if fdefn (sb!kernel:fun-code-header fdefn)))
+                  (debug-info (if code (sb!kernel:%code-debug-info code)))
+                  (debug-source (if debug-info
+                                    (sb!c::debug-info-source debug-info)))
+                  (namestring (if debug-source
+                                  (sb!c::debug-source-namestring debug-source))))
+             namestring)))
+    (and
+     ;; There's garbage in various places when the first DEFUN runs in
+     ;; cold-init.
+     sb!kernel::*cold-init-complete-p*
+     (typep warning 'redefinition-with-defun)
+     (let ((old-fdefn
+            (function-redefinition-warning-old-fdefinition warning))
+           (new-fdefn
+            (redefinition-with-defun-new-fdefinition warning)))
+       ;; Replacing a compiled function with a compiled function is
+       ;; clearly uninteresting, and we'll say arbitrarily that
+       ;; replacing an interpreted function with an interpreted
+       ;; function is uninteresting, too, but leave out the
+       ;; compiled-to-interpreted case.
+       (when (or (typep
+                  old-fdefn
+                  '(or #!+sb-eval sb!eval:interpreted-function))
+                 (and (typep old-fdefn
+                             '(and compiled-function
+                               (not funcallable-instance)))
+                      ;; Since this is a REDEFINITION-WITH-DEFUN,
+                      ;; NEW-FDEFN can't be a FUNCALLABLE-INSTANCE.
+                      (typep new-fdefn 'compiled-function)))
+         (let* ((old-namestring (fdefinition-file-namestring old-fdefn))
+                (new-namestring
+                 (or (fdefinition-file-namestring new-fdefn)
+                     (let ((srcloc
+                            (redefinition-with-defun-new-location warning)))
+                       (if srcloc
+                            (sb!c::definition-source-location-namestring
+                                srcloc))))))
+           (and old-namestring
+                new-namestring
+                (equal old-namestring new-namestring))))))))
+
+(defun uninteresting-generic-function-redefinition-p (warning)
+  (and (typep warning 'redefinition-with-defgeneric)
+       (let* ((old-fdefn
+               (function-redefinition-warning-old-fdefinition warning))
+              (old-location
+               (if (typep old-fdefn 'generic-function)
+                   (sb!pcl::definition-source old-fdefn)))
+              (old-namestring
+               (if old-location
+                   (sb!c:definition-source-location-namestring old-location)))
+              (new-location
+               (redefinition-with-defgeneric-new-location warning))
+              (new-namestring
+               (if new-location
+                   (sb!c:definition-source-location-namestring new-location))))
+         (and old-namestring
+              new-namestring
+              (equal old-namestring new-namestring)))))
+
+(defun uninteresting-method-redefinition-p (warning)
+  (and (typep warning 'redefinition-with-defmethod)
+       (let* ((old-method (redefinition-with-defmethod-old-method warning))
+              (old-location (sb!pcl::definition-source old-method))
+              (old-namestring (if old-location
+                                  (sb!c:definition-source-location-namestring
+                                      old-location)))
+              (new-location (redefinition-with-defmethod-new-location warning))
+              (new-namestring (if new-location
+                                  (sb!c:definition-source-location-namestring
+                                      new-location))))
+         (and new-namestring
+              old-namestring
+              (equal new-namestring old-namestring)))))
+
+(deftype uninteresting-redefinition ()
+  '(or (satisfies uninteresting-ordinary-function-redefinition-p)
+       (satisfies uninteresting-generic-function-redefinition-p)
+       (satisfies uninteresting-method-redefinition-p)))
+
+(define-condition redefinition-with-deftransform (redefinition-warning)
+  ((transform :initarg :transform
+              :reader redefinition-with-deftransform-transform))
+  (:report (lambda (warning stream)
+             (format stream "Overwriting ~S"
+                     (redefinition-with-deftransform-transform warning)))))
+\f
+;;; Various other STYLE-WARNINGS
+(define-condition dubious-asterisks-around-variable-name
+    (style-warning simple-condition)
+  ()
+  (:report (lambda (warning stream)
+             (format stream "~@?, even though the name follows~@
+the usual naming convention (names like *FOO*) for special variables"
+                     (simple-condition-format-control warning)
+                     (simple-condition-format-arguments warning)))))
+
+(define-condition asterisks-around-lexical-variable-name
+    (dubious-asterisks-around-variable-name)
+  ())
+
+(define-condition asterisks-around-constant-variable-name
+    (dubious-asterisks-around-variable-name)
+  ())
+
+;; We call this UNDEFINED-ALIEN-STYLE-WARNING because there are some
+;; subclasses of ERROR above having to do with undefined aliens.
+(define-condition undefined-alien-style-warning (style-warning)
+  ((symbol :initarg :symbol :reader undefined-alien-symbol))
+  (:report (lambda (warning stream)
+             (format stream "Undefined alien: ~S"
+                     (undefined-alien-symbol warning)))))
+
+#!+sb-eval
+(define-condition lexical-environment-too-complex (style-warning)
+  ((form :initarg :form :reader lexical-environment-too-complex-form)
+   (lexenv :initarg :lexenv :reader lexical-environment-too-complex-lexenv))
+  (:report (lambda (warning stream)
+             (format stream
+                     "~@<Native lexical environment too complex for ~
+                         SB-EVAL to evaluate ~S, falling back to ~
+                         SIMPLE-EVAL-IN-LEXENV.  Lexenv: ~S~:@>"
+                     (lexical-environment-too-complex-form warning)
+                     (lexical-environment-too-complex-lexenv warning)))))
+
+;; Although this has -ERROR- in the name, it's just a STYLE-WARNING.
+(define-condition character-decoding-error-in-comment (style-warning)
+  ((stream :initarg :stream :reader decoding-error-in-comment-stream)
+   (position :initarg :position :reader decoding-error-in-comment-position))
+  (:report (lambda (warning stream)
+             (format stream
+                      "Character decoding error in a ~A-comment at ~
+                      position ~A reading source stream ~A, ~
+                      resyncing."
+                      (decoding-error-in-comment-macro warning)
+                      (decoding-error-in-comment-position warning)
+                      (decoding-error-in-comment-stream warning)))))
+
+(define-condition character-decoding-error-in-macro-char-comment
+    (character-decoding-error-in-comment)
+  ((char :initform #\; :initarg :char
+         :reader character-decoding-error-in-macro-char-comment-char)))
+
+(define-condition character-decoding-error-in-dispatch-macro-char-comment
+    (character-decoding-error-in-comment)
+  ;; ANSI doesn't give a way for a reader function invoked by a
+  ;; dispatch macro character to determine which dispatch character
+  ;; was used, so if a user wants to signal one of these from a custom
+  ;; comment reader, he'll have to supply the :DISP-CHAR himself.
+  ((disp-char :initform #\# :initarg :disp-char
+              :reader character-decoding-error-in-macro-char-comment-disp-char)
+   (sub-char :initarg :sub-char
+             :reader character-decoding-error-in-macro-char-comment-sub-char)))
+
+(defun decoding-error-in-comment-macro (warning)
+  (etypecase warning
+    (character-decoding-error-in-macro-char-comment
+     (character-decoding-error-in-macro-char-comment-char warning))
+    (character-decoding-error-in-dispatch-macro-char-comment
+     (format
+      nil "~C~C"
+      (character-decoding-error-in-macro-char-comment-disp-char warning)
+      (character-decoding-error-in-macro-char-comment-sub-char warning)))))
+
+(define-condition deprecated-eval-when-situations (style-warning)
+  ((situations :initarg :situations
+               :reader deprecated-eval-when-situations-situations))
+  (:report (lambda (warning stream)
+             (format stream "using deprecated EVAL-WHEN situation names~{ ~S~}"
+                     (deprecated-eval-when-situations-situations warning)))))
+
+(define-condition proclamation-mismatch (style-warning)
+  ((name :initarg :name :reader proclamation-mismatch-name)
+   (old :initarg :old :reader proclamation-mismatch-old)
+   (new :initarg :new :reader proclamation-mismatch-new)))
+
+(define-condition type-proclamation-mismatch (proclamation-mismatch)
+  ()
+  (:report (lambda (warning stream)
+             (format stream
+                     "The new TYPE proclamation~% ~S for ~S does not ~
+                     match the old TYPE proclamation ~S"
+                     (proclamation-mismatch-new warning)
+                     (proclamation-mismatch-name warning)
+                     (proclamation-mismatch-old warning)))))
+
+(define-condition ftype-proclamation-mismatch (proclamation-mismatch)
+  ()
+  (:report (lambda (warning stream)
+             (format stream
+                     "The new FTYPE proclamation~% ~S for ~S does not ~
+                     match the old FTYPE proclamation ~S"
+                     (proclamation-mismatch-new warning)
+                     (proclamation-mismatch-name warning)
+                     (proclamation-mismatch-old warning)))))
 \f
 ;;;; restart definitions
 
@@ -1246,15 +1616,16 @@ the value of the variable. No associated restarts."))
    CONTROL-ERROR if none exists."
   (invoke-restart (find-restart-or-control-error 'muffle-warning condition)))
 
+(defun try-restart (name condition &rest arguments)
+  (let ((restart (find-restart name condition)))
+    (when restart
+      (apply #'invoke-restart restart arguments))))
+
 (macrolet ((define-nil-returning-restart (name args doc)
              #!-sb-doc (declare (ignore doc))
              `(defun ,name (,@args &optional condition)
                 #!+sb-doc ,doc
-                ;; FIXME: Perhaps this shared logic should be pulled out into
-                ;; FLET MAYBE-INVOKE-RESTART? See whether it shrinks code..
-                (let ((restart (find-restart ',name condition)))
-                  (when restart
-                    (invoke-restart restart ,@args))))))
+                (try-restart ',name condition ,@args))))
   (define-nil-returning-restart continue ()
     "Transfer control to a restart named CONTINUE, or return NIL if none exists.")
   (define-nil-returning-restart store-value (value)