#11555: catch _|_ breaks at -O1 -------------------------------------+------------------------------------- Reporter: slyfox | Owner: Type: bug | Status: patch Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 8.0.1-rc2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1973 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"30ee9102db2f16894912e19b9d16156824611bbb/ghc" 30ee9102/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="30ee9102db2f16894912e19b9d16156824611bbb" Make `catch` lazy in the action Previously ```lang=haskell catch (error "uh oh") (\(_ :: SomeException) -> print "it failed") ``` would unexpectedly fail with "uh oh" instead of the handler being run due to the strictness of `catch` in its first argument. See #11555 for details. Test Plan: Validate Reviewers: austin, hvr, simonpj Reviewed By: simonpj Subscribers: simonpj, thomie Differential Revision: https://phabricator.haskell.org/D1973 GHC Trac Issues: #11555 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11555#comment:20> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler