bytecmp accepts invalid mapcar

> (defun bah () (mapcar #'(lambda (arg) arg)))
BAH
> (bah)
Condition of type: SIMPLE-PROGRAM-ERROR
MAP*: Too few arguments

Available restarts:

1. (RESTART-TOPLEVEL) Go back to Top-Level REPL.

Broken at BAH. In: #<process TOP-LEVEL>.
>> :r1
> (compile 'bah)
;;; OPTIMIZE levels: Safety=2, Space=0, Speed=3, Debug=3
;;;
;;; Error:
;;;   * The macro form (MAPCAR #'(LAMBDA (ARG) ARG)) was not expanded successfully.
;;; Error detected:
;;; The function PROGRAM-ERROR is undefined.
BAH
T
T
>

Compiler complains, that it couldn't expand the mapcar, yet bytecmp accepts such construct.

sbcl's response:

* (defun bah () (mapcar #'(lambda (arg) arg)))
; in: DEFUN BAH
;     (MAPCAR #'(LAMBDA (ARG) ARG))
; 
; caught WARNING:
;   The function was called with one argument, but wants at least two.
; 
; compilation unit finished
;   caught 1 WARNING condition
* (bah)
debugger invoked on a SB-INT:SIMPLE-PROGRAM-ERROR in thread
#<THREAD "main thread" RUNNING {1002AF4453}>:
  invalid number of arguments: 1

Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL.

restarts (invokable by number or by possibly-abbreviated name):
  0: [ABORT] Exit debugger, returning to top level.

(MAPCAR #<FUNCTION (LAMBDA (ARG) :IN BAH) {100477FDBB}>) [tl,external]
0] 

(in all cases if defun is successful calling the function fails with the appropriate error)

Proposed solution:

• unify behaviour by causing an error on bytecmp too
• document this behavior

ccl signals an error

changed milestone to %ECL 16.2.0

fixed in develop

closed