[GHC] #16322: "deriving newtype instance" generates an infinite loop
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Fri Feb 15 19:49:35 UTC 2019
#16322: "deriving newtype instance" generates an infinite loop
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Reporter: paf31 | Owner: (none)
Type: bug | Status: infoneeded
Priority: normal | Milestone:
Component: Compiler | Version: 8.6.3
Resolution: | Keywords:
Operating System: Unknown/Multiple | Architecture:
| Unknown/Multiple
Type of failure: None/Unknown | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s):
Wiki Page: |
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Comment (by paf31):
To be clear, I now understand why this code should fail to compile,
because the instance precondition should be `C (X String a) b`, and not `C
a b`. But I still think it shouldn't loop at runtime.
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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16322#comment:6>
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