#14163: Stack Overflow with ApplicativeDo -------------------------------------+------------------------------------- Reporter: lippling | Owner: simonmar Type: bug | Status: new Priority: high | Milestone: 8.2.2 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: ApplicativeDo Operating System: MacOS X | Architecture: x86_64 Type of failure: Compile-time | (amd64) crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * priority: normal => high * milestone: => 8.2.2 Old description:
I tried to compile one of our server applications with 8.2.1 (which compiles fine with 8.0.2).
The compilation runs smoothly, but when it reaches a specific file, the RAM usage goes up to > 20GB pretty fast on my 16GB machine and the GHC process gets terminated with a stack overflow error.
I tried to find a minimal example that causes this behavior:
{{{ #!/usr/bin/env stack -- stack --resolver nightly-2017-08-25 script
{-# LANGUAGE ApplicativeDo #-}
x = do (a, _) <- undefined (b, _) <- undefined (c, _) <- undefined undefined
main = undefined }}}
It only happens with at least 3 of these pattern matches.
New description: I tried to compile one of our server applications with 8.2.1 (which compiles fine with 8.0.2). The compilation runs smoothly, but when it reaches a specific file, the RAM usage goes up to > 20GB pretty fast on my 16GB machine and the GHC process gets terminated with a stack overflow error. I tried to find a minimal example that causes this behavior: {{{#!hs #!/usr/bin/env stack -- stack --resolver nightly-2017-08-25 script {-# LANGUAGE ApplicativeDo #-} x = do (a, _) <- undefined (b, _) <- undefined (c, _) <- undefined undefined main = undefined }}} It only happens with at least 3 of these pattern matches. -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14163#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler