incorrect compilation of known local calls

[felix winkelmann]

Locally bound known procedures are marked during closure conversion as "customizable" when all call sites are known which allows passing arguments directly instead of using the argc/argvector convention. The compiler does this marking on the first encounter of a call to such a procedure with matches the signature. But if a later call does not match the lambda-list the mark is still active, even though that later call uses the standard convention and the callee will be compiled with a customizable arglist. This means that the later call uses the wrong calling convention resulting in a crash.

Here an example:

(define (foo x)
  (define (bar x y)
    (let ((k (identity bar)))
      (k 1))
    (if (> x 1) (bar (sub1 x) y)))
  (bar 2 x))
(foo '(a b))

This bug was detected in 6.0.0 but seems already to be present in earlier 5.x.x releases.

A remedy would be to drop the mark when not all call sites have arguments that match the lambda list of the callee.

[felix winkelmann]

Fixed in 5e3d5620e2481bac26f21239962a709d68beea77 for C6.