setters like set-cdr! don't invalidate type information

[sjamaan]

The following program, when compiled with specialization, prints {{#t}}. It prints #f in all other cases:

(let ((x (list 'a)))
  (set-cdr! x x)
  (print (list? x)))

If possible, set-car! and set-cdr! should have roughly the same effect as set! (and so should vector-set! but I couldn't reproduce a similar error with that, so I guess that's already taken care of, somehow)

I'll look into it in more detail but wanted to create a ticket so we don't forget about this.

[felix]

It looks like smash-component-types! needs not only to smash components but also change list and list-of types to (pair ...), since set-cdr! may convert a proper list into an improper one.

[felix]

patch submitted to chicken-hackers

[sjamaan]

This patch fixes it

[felix]

Milestone 4.8.0 deleted