#12151: GHC 8 allows ambiguous type without AllowAmbiguousTypes -------------------------------------+------------------------------------- Reporter: thomie | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.0.1 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect | Unknown/Multiple warning at compile-time | Test Case: Blocked By: | Blocking: Related Tickets: #7437 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"85aa6ef09346e841abf4e089b24c7f783286cd74/ghc" 85aa6ef0/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="85aa6ef09346e841abf4e089b24c7f783286cd74" Check generic-default method for ambiguity Fixes Trac #7497 and #12151. In some earlier upheaval I introduced a bug in the ambiguity check for genreric-default method. This patch fixes it. But in fixing it I realised that the sourc-location of any such error message was bogus, so I fixed that too, which involved a slightly wider change; see the comments with TcMethInfo. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12151#comment:1> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler