Bug 16940 - Receive on a BufferBlock blocks indefinitely
Summary: Receive on a BufferBlock blocks indefinitely
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: 3.2.x
Hardware: PC Windows
: Normal normal
Target Milestone: Untriaged
Assignee: Jérémie Laval
Depends on:
Reported: 2013-12-23 04:29 UTC by Fengyun RAO
Modified: 2015-12-24 15:05 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Fengyun RAO 2013-12-23 04:29:24 UTC
Example code:

var bufferBlock = new BufferBlock<int>();
for (int i = 0; i < 2; i++)


if (await bufferBlock.OutputAvailableAsync())

Under .NET, this outputs "0 1" and exits. 
Under Mono 3.2.3 on Linux or Windows, this outputs "0" and hangs indefinitely.

It seems something went wrong on bufferBlock.OutputAvailableAsync().
Comment 1 Miguel de Icaza [MSFT] 2015-12-24 15:05:22 UTC
This has been fixed by bringing the Reference Source.