#11518: Test TcCoercibleFail hangs with substitution sanity checks enabled -------------------------------------+------------------------------------- Reporter: niteria | Owner: niteria Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): Replying to [comment:11 niteria]:

It's always been 100: [0b7e538a09bc958474ec704063eaa08836e9270e].

No. Before that commit, `checkRecTc` allowed one unwrapping. The second failed (because the `TyCon` was in the `NameSet` nearby. But there's also a reference to the ticket that inspired the increase, which is helpful. I guess, in the end, we're never going to get this number correct. We could just have a flag for it, as suggested in the code there. Then, for this test, we use the flag. In the end, we're talking about a slowdown that affect only `DEBUG` compilers, yes? So I'm more worried about getting the test to pass before the end of the universe than in actually removing the exponential behavior -- especially given that the user's program indeed introduces the exponential behavior. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11518#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler