Bug when using TimerManager/GHC.Event ?
It was suggested on #haskell that this is a bug and that I should report it here. Hopefully this is the simplest possible example that shows the issue. The code sample I got from a StackOverflow answer (https://stackoverflow.com/a/25488677) which I found just trying to learn how to use GHC.Event properly so presumably, and it seemed to work there, so I assume it is still valid code (but let me know if not!).
Minimal example repo is here: https://github.com/ddellacosta/timermanager-bug, please see Main.hs
I'm on on OS X 10.13.6, and hopefully the shell dump below combined with the repo above gives you everything else you need:
$ cabal new-configure
Resolving dependencies...
Build profile: -w ghc-8.4.3 -O1
In order, the following would be built (use -v for more details):
- timermanager-bug-0.1.0.0 (exe:timermanager-bug) (first run)
$ cabal new-build
Build profile: -w ghc-8.4.3 -O1
In order, the following will be built (use -v for more details):
- timermanager-bug-0.1.0.0 (exe:timermanager-bug) (first run)
Configuring executable 'timermanager-bug' for timermanager-bug-0.1.0.0..
clang: warning: argument unused during compilation: '-nopie' [-Wunused-command-line-argument]
Preprocessing executable 'timermanager-bug' for timermanager-bug-0.1.0.0..
Building executable 'timermanager-bug' for timermanager-bug-0.1.0.0..
[1 of 1] Compiling Main ( Main.hs, /Users/ddellacosta/code/timermanager-bug/dist-newstyle/build/x86_64-osx/ghc-8.4.3/timermanager-bug-0.1.0.0/x/timermanager-bug/build/timermanager-bug/timermanager-bug-tmp/Main.o )
Linking /Users/ddellacosta/code/timermanager-bug/dist-newstyle/build/x86_64-osx/ghc-8.4.3/timermanager-bug-0.1.0.0/x/timermanager-bug/build/timermanager-bug/timermanager-bug ...
clang: warning: argument unused during compilation: '-nopie' [-Wunused-command-line-argument]
clang: warning: argument unused during compilation: '-nopie' [-Wunused-command-line-argument]
$ cabal new-exec timermanager-bug
timermanager-bug: user error (Pattern match failure in do expression at libraries/base/GHC/Event/Thread.hs:216:3-10)
$Let me know if there's any more information I can supply! Apologies if this is not actually a bug but something I'm doing wrong! Thanks!
Trac metadata
| Trac field | Value |
|---|---|
| Version | 8.4.3 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | Unknown/Multiple |
| Architecture |