juvix compile loops on filter (const false) [] (and other functions using specialize pragma)

[paulcadman]

To reproduce:

module M;

import Stdlib.Prelude open;

main : List Nat := filter (const false) [];

Then compile:

juvix compile native M.juvix

Expected

The module compiles.

Actual

The compiler loops.

NB:

module M;

import Stdlib.Prelude open;

main : List Nat := filter (const true) [];

works fine.

The compilation works if the optimiser is switched off:

juvix compile native -O0 M.juvix

Other ways to reproduce

This bug is also triggered with other functions, for example with the following definition of find. It seems to be triggered by some combination of the specialize pragma and the use of const false.

module Find;

import Stdlib.Prelude open;

{-# specialize: [predicate] #-}
myFind {A} (predicate : A → Bool) : List A → Maybe A
  | nil := nothing
  | (x :: xs) :=
    if
      | predicate x := just x
      | else := myFind predicate xs;

main : Maybe Nat := myFind (const false) [1;2;3];