[racket] weird error with typed racket, submodules, and math/array

If I have this program:
#lang typed/racket
(require math/array)
(module+ test
  (require math/array)
  (array #[#[#f #f #f]
           #[#f #f #f]
           #[#f #f #f]])
  )
Then it gives me this error:
Type Checker: missing type for identifier;
 consider using `require/typed' to import it
  identifier: unsafe-list->array
  from module: typed-array-struct.rkt in: unsafe-list->array

If I take it out of the module+ test the error goes away, but what’s really weird is that if I take out the first (require math/array), then the error also goes away.  

And also I just curious, how does type checking work with module+ anyway?  

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