Original bug ID: 6275
Reporter: @lpw25
Assigned to: @garrigue
Status: closed (set by @xavierleroy on 2015-12-11T18:25:30Z)
Resolution: fixed
Priority: normal
Severity: minor
Version: 4.01.0
Fixed in version: 4.01.1+dev
Category: typing
Related to: #5985
Monitored by: @yallop @hcarty

Bug description

Soundness bug related to type constraints reported by art-w on reddit:

        OCaml version 4.02.0+dev2-2013-09-12
 
# type 'x t = A of 'a constraint 'x = [< `X of 'a ] ;;
type 'b t = A of 'a constraint 'b = [< `X of 'a ]
# let magic (x : 'a) = 
    let A x = A x in
      x;;
    val magic : 'a -> 'b = <fun>
# (magic 0: string);;
 
Process ocaml-toplevel segmentation fault