Bug 57069 - WaitHandle.SignalAndWait is broke
Summary: WaitHandle.SignalAndWait is broke
Alias: None
Product: Runtime
Classification: Mono
Component: io-layer ()
Version: 5.0 (2017-02)
Hardware: PC Mac OS
: Normal major
Target Milestone: ---
Assignee: Ludovic Henry
Depends on:
Reported: 2017-06-01 19:20 UTC by Jonathan Chambers
Modified: 2017-06-05 19:18 UTC (History)
4 users (show)

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

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Description Jonathan Chambers 2017-06-01 19:20:34 UTC
Run the follow test case. It hangs in Mono 5.0+. This is a regression from Mono 4.8

using System;
using System.Threading;

internal class Program
    public static void Main (string[] args)
        using (var eventToSignal = new AutoResetEvent (false))
        using (var eventToWait = new AutoResetEvent (false))
            eventToWait.Set ();

            var res1 = WaitHandle.SignalAndWait (eventToSignal, eventToWait);
            Console.WriteLine ("res1: " + res1);

            var res2 = eventToSignal.WaitOne ();
            Console.WriteLine ("res2: " + res2);
Comment 1 Jonathan Chambers 2017-06-01 19:28:04 UTC
This runs fine on Mono with Windows, so this looks like a w32 layer issue.
Comment 2 Ludovic Henry 2017-06-05 19:18:33 UTC
This is fixed with https://github.com/mono/mono/pull/4973