Modifying TVar after calling always causes freeze/spin in GHCi
The attached code, if run under GHCi, causes GHCi to freeze while spinning the CPU. It works correctly when compiled, or if the ">> modifyTVar" part of f is commented out.
(For the curious: Yes, I believed always does what check does. Thankfully nothing had made its way into production code, because of this bug. The documentation should probably be clarified.)
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.12.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | GHCi |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |