#14873: GHC HEAD regression (piResultTy) -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: Component: Compiler (Type | Version: 8.5 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"3d252037234ce48f9bdada7d5c9b1d8eba470829/ghc" 3d252037/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="3d252037234ce48f9bdada7d5c9b1d8eba470829" Respect Note [The tcType invariant] I tried to do this with commit 0a12d92a8f65d374f9317af2759af2b46267ad5c Author: Simon Peyton Jones <simonpj@microsoft.com> Date: Wed Dec 13 12:53:26 2017 +0000 Further improvements to well-kinded types The typechecker has the invariant that every type should be well- kinded as it stands, without zonking. See Note [The well-kinded type invariant] in TcType. That invariant was not being upheld, which led to Trac #14174. I fixed part of it, but T14174a showed that there was more. This patch finishes the job. But I didn't get it quite right as Trac #14873 showed. This patch fixes the problem; although I am still a bit unhappy. (See "A worry" in the HsApp case of tc_infer_hs_type.) }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14873#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler