#13730: Running GLUT code in GHCi yields NSInternalInconsistencyException ----------------------------------------+------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: GHCi | Version: 8.0.2 Keywords: | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: GHCi crash Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ----------------------------------------+------------------------------- I tried running some `GLUT` code in macOS Sierra (Version 10.12.5 (16F73)) and ran into a strange error. If you're willing to use `cabal-install`, you can just do this: {{{ $ cabal install GLFW-0.5.2.5 }}} And run this module in with `runghc`: {{{#!hs -- GLUT.hs module Main where import Graphics.UI.GLUT (($=), getArgsAndInitialize, createWindow, displayCallback, mainLoop) main :: IO () main = do (_progName, _args) <- getArgsAndInitialize _window <- createWindow "Hello World" displayCallback $= return () mainLoop }}} {{{ $ runghc GLUT.hs 2017-05-19 12:03:02.199 ghc[24628:669385] GLUT Fatal Error: internal error: NSInternalInconsistencyException, reason: nextEventMatchingMask should only be called from the Main Thread! }}} On the other hand, compiling and running the executable works without issue. Alternatively, you can compile the attached files, which require no dependencies: {{{ $ ghc HsGLUT.c GLUT2.hs [1 of 1] Compiling Main ( GLUT2.hs, GLUT2.o ) Linking GLUT2 ... $ ghci HsGLUT.o GLUT2.hs GHCi, version 8.0.2: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /Users/rscott/.ghci [1 of 1] Compiling Main ( GLUT2.hs, interpreted ) Ok, modules loaded: Main. λ> main 2017-05-19 12:06:15.365 ghc[24671:670166] GLUT Fatal Error: internal error: NSInternalInconsistencyException, reason: nextEventMatchingMask should only be called from the Main Thread! }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13730 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler