#10356: Couldn't match type ‘a’ with ‘Int’ / ‘a’ is untouchable / inside the constraints () -------------------------------------+------------------------------------- Reporter: radix | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.1 Keywords: | Operating System: Unknown/Multiple Architecture: x86_64 | Type of failure: Compile-time (amd64) | crash Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+------------------------------------- Sadly I'm a Haskell newbie, so this won't be a very good bug report, but I am working on a codebase and I triggered a GHC bug (at least according to GHC itself). {{{ Building json-log-viewer-0.0.1... Preprocessing executable 'json-log-viewer' for json-log-viewer-0.0.1... [3 of 3] Compiling Main ( src/Main.hs, dist/build/json-log- viewer/json-log-viewer-tmp/Main.o ) src/Main.hs:316:41: Couldn't match type ‘a’ with ‘Int’ ‘a’ is untouchable inside the constraints () bound by the inferred type of refreshMessages :: IO () at src/Main.hs:(300,7)-(324,48)ghc: panic! (the 'impossible' happened) (GHC version 7.10.1 for x86_64-apple-darwin): No skolem info: a_al2w[sk] Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} I saved the state of the code in a git branch and put it here: https://github.com/radix/json-log-viewer/tree/ghc-bug I'll also attach my list of cabal dependencies installed. The only tricky one is that I'm working off of an unreleased version of `vty-ui`, at this revision: https://github.com/jtdaugherty/vty- ui/commit/c3a0c4b660119a4d5862a6f549a98739a3fc5fa7 I also don't know if the program is "valid" -- I'm in the middle of a refactor, and it's a big cluttered program that I know is very poorly written. Sorry about that. I would not usually report a bug in such a situation but the compiler implored me to, so I am. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10356 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler