resource busy (file is locked) with multi-threaded file ops

The sample program attached creates 10 worker threads, each of which takes a different file name. Each worker thread then writes the file, reads the file, writes the file and so on. File operations use *strict IO*.

When compiled without -threaded everything is ok, that is, the program goes on forever without any error messages.

But with -threaded, the program quickly fails with ERROR in worker 4: 4: openBinaryFile: resource busy (file is locked).

Tested under Mac OSX 10.8.2 and Linux. Tested with both GHC 7.6.1 and 7.6.2.

I could reproduce the bug without +RTS -N -RTS and with this RTS option. A colleague of mine reports that it needs +RTS -N2 -RTS to reproduce the bug.

Trac metadata

Trac field	Value
Version	7.6.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Runtime System
Test case
Differential revisions
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Blocking
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Operating system
Architecture

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