System.Runtime.CompilerServices.Unsafe not suppot .NET Core 2.x apps

[WeihanLi]

Description

When I try to upgrade System.Runtime.CompilerServices.Unsafe package from 5.0.0 to 6.0.0, it seemed the package does not support for .NET Core 2.x apps. Maybe this is by design?

System.Runtime.CompilerServices.Unsafe doesn't support netcoreapp2.1

Reproduction Steps

Create a empty .NET Core 2.x app and add package reference for System.Runtime.CompilerServices.Unsafe with 6.0.0 version

Expected behavior

As a library, maybe should support all the targets

Actual behavior

.NET Core app 3.1 and below are not supported

Regression?

No response

Known Workarounds

Downgrade to 5.0.0

Configuration

.NET Core app 2.1/2.2

Other information

No response

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Issue Details

---

Description

When I try to upgrade System.Runtime.CompilerServices.Unsafe package from 5.0.0 to 6.0.0, it seemed the package does not support for .NET Core 2.x apps. Maybe this is by design?

System.Runtime.CompilerServices.Unsafe doesn't support netcoreapp2.1

Reproduction Steps

Create a empty .NET Core 2.x app and add package reference for System.Runtime.CompilerServices.Unsafe with 6.0.0 version

Expected behavior

As a library, maybe should support all the targets

Actual behavior

.NET Core app 3.1 and below are not supported

Regression?

No response

Known Workarounds

Downgrade to 5.0.0

Configuration

.NET Core app 2.1/2.2

Other information

No response

Author:	WeihanLi
Assignees:	-
Labels:	area-System.Runtime.CompilerServices, untriaged
Milestone:	-

[danmoseley]

Hello, we dropped support for 2.1 as it is out of support.
Can you updated to 6.0?
If not you will have to use the older package version, although it is out of support.

[danmoseley]

https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core

[WeihanLi]

Hi @danmoseley got it, thanks

[WeihanLi]

Think it's better to remove the netstandard2.0 support, since the .NET Core 2.x apps are not supported and already has netcoreapp3.1 target

[GrabYourPitchforks]

@WeihanLi The netstandard2.0 target will remain for a while longer. netstandard2.0 is supported by runtimes beyond .NET Framework and .NET Core, and those runtimes may still be supported by their maintainers. See the table at https://docs.microsoft.com/dotnet/standard/net-standard#net-implementation-support for more information.

[WeihanLi]

@GrabYourPitchforks thanks, since we had a netstandard2.0 target support and .NET Core 2.x had support for netstandard2.0, though .NET Core 2.x had been out of support, I think it would be better if we could have .NET Core 2.x app support