Re: [GHC] #15370: Typed hole panic on GHC 8.6 (tcTyVarDetails)

#15370: Typed hole panic on GHC 8.6 (tcTyVarDetails) -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: Tritlo Type: bug | Status: patch Priority: high | Milestone: 8.6.1 Component: Compiler (Type | Version: 8.4.3 checker) | Keywords: TypeInType, Resolution: | TypedHoles 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 Krzysztof Gogolewski ): In [changeset:"0dc86f6bc454253969dedc31bed477eded4cf82d/ghc" 0dc86f6b/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="0dc86f6bc454253969dedc31bed477eded4cf82d" Clone relevant constraints to avoid side-effects on HoleDests. Fixes #15370. Summary: When looking for valid hole fits, the constraints relevant to the hole may sometimes contain a HoleDest. Previously, these were not cloned, which could cause the filling of filled coercion hole being, which would cause an assert to fail. This is now fixed. Test Plan: Regression test included. Reviewers: simonpj, bgamari, goldfire Reviewed By: simonpj Subscribers: rwbarton, thomie, carter GHC Trac Issues: #15370 Differential Revision: https://phabricator.haskell.org/D5004 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15370#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler