Ran into some unexpected behavior today. Quoted values do not seem to
be garbage collected when there are only weak references. Is this
correct behavior?

Here's an example program:

#lang racket/base

(define key1 (list 1))
(define key2 '(1))

(define hash1 (make-weak-hash (list (cons key1 1))))
(define hash2 (make-weak-hash (list (cons key2 1))))


(set! key1 null)
(set! key2 null)

(collect-garbage) ; I tried a range of gc pressure here with no difference


I expected it to produce:

'#hash(((1) . 1))
'#hash(((1) . 1))

But instead got:

'#hash(((1) . 1))
'#hash(((1) . 1))
'#hash(((1) . 1))

Searching through the docs I found the following line [1] that maybe
explains the behavior (but I'm not sure)?

"Values produced by quote remain reachable when the quote expression
itself is reachable."

Is this saying that since the quoted value is reachable via the weak
reference, it is considered reachable?

[1] http://docs.racket-lang.org/reference/eval-model.html?#%28part._gc-model%29

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