racket / racket/typed-racket

Misprediction of predicate on substruct

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unsound
Dominant language
Racket
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Forks
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Merged PRs (30d)
2

Description

#lang typed/racket #:no-optimize

(struct (A) foo ([x : A]))

(struct (A) baz foo ())

(define (f [i : Integer]) : (foo Integer)
  (baz i))

(if (baz? (f 1)) 1 2)

Behaves differently under optimization. Reported by Antonio Menezes Leitao on the mailing list.

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Research direction

Run the supplied Typed Racket example with and without optimization and compare the result of the baz? predicate. Trace the predicate handling for the foo/baz substruct relationship; done means the optimized and unoptimized cases agree on the correct predicate result.

Written by the indexing model from the issue text.

Assessment

Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
28/100

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