Bug 35088 - Incorrect CS0420 warning when using volatile variable with Interlocked APIs
Summary: Incorrect CS0420 warning when using volatile variable with Interlocked APIs
Status: NEW
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: All All
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2015-10-20 09:06 UTC by Alexander Köplinger [MSFT]
Modified: 2015-10-20 09:06 UTC (History)
1 user (show)

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

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Description Alexander Köplinger [MSFT] 2015-10-20 09:06:22 UTC
Repro code:

> using System.Threading;
> public class Test
> {
>    volatile int foo;
>    void Bar()
>    {
>       Interlocked.CompareExchange(ref foo, 0, 1);
>    }
> }


> mcs -t:library test.cs


> test.cs(9,39): warning CS0420: `Test.foo': A volatile field references will not be treated as volatile

According to https://msdn.microsoft.com/en-us/library/4bw5ewxy.aspx this warning shouldn't be raised when using the Interlocked.* APIs. csc and Roslyn don't generate a warning.

Nit: there's a typo in the warning message: "references" -> "reference"