Using the Shake repo (https://github.com/ndmitchell/shake.git) at commit d7fa04 and GHC 7.10 RC3 or GHC HEAD, if I {{cabal test}} I get the error: ``` ## BUILD oracle --quiet *str-int TESTS FAILED shake-test: Expected an exception but succeeded ``` Discussion about this issue can be found on the mailing list: http://osdir.com/ml/general/2015-03/msg25847.html GHC generates the Core: ``` case (\_ -> error "here") of {} ``` This is invalid GHC Core. I intend to track down a minimal example shortly. <details><summary>Trac metadata</summary> | Trac field | Value | | ---------------------- | -------------------- | | Version | 7.8.4 | | Type | Bug | | TypeOfFailure | OtherFailure | | Priority | high | | Resolution | Unresolved | | Component | Compiler | | Test case | | | Differential revisions | | | BlockedBy | | | Related | | | Blocking | | | CC | ndmitchell@gmail.com | | Operating system | | | Architecture | | </details> <!-- {"blocked_by":[],"summary":"Invalid core generated with GHC 7.10 RC3","status":"New","operating_system":"","component":"Compiler","related":[],"milestone":"","resolution":"Unresolved","owner":{"tag":"Unowned"},"version":"7.8.4","keywords":[],"differentials":[],"test_case":"","architecture":"","cc":["ndmitchell@gmail.com"],"type":"Bug","description":"Using the Shake repo (https://github.com/ndmitchell/shake.git) at commit d7fa04 and GHC 7.10 RC3 or GHC HEAD, if I {{cabal test}} I get the error:\r\n\r\n{{{\r\n## BUILD oracle --quiet *str-int\r\nTESTS FAILED\r\nshake-test: Expected an exception but succeeded\r\n}}}\r\n\r\nDiscussion about this issue can be found on the mailing list: http://osdir.com/ml/general/2015-03/msg25847.html\r\n\r\nGHC generates the Core:\r\n\r\n{{{\r\ncase (\\_ -> error \"here\") of {}\r\n}}}\r\n\r\nThis is invalid GHC Core. I intend to track down a minimal example shortly.","type_of_failure":"OtherFailure","blocking":[]} -->