efcore: Microsoft.EntityFrameworkCore.SQLite on Android 7+ not working

I was successfully using Microsoft.EntityFrameworkCore.SQLite v.1.1.2 in a Xamarin.Android project. But for Android 7+, the app crashes with unauthorized access to "/system/lib64/libsqlite.so" (as reported here).

So I updated to version v2.0.0-preview1-final as this should fix the issue. However, this results in other problems like the following where the app compiled, but crashed while deploying/starting on the emulator:

...
06-21 09:58:18.970 D/Mono    ( 3632): Assembly Loader probing location: 'System.Runtime.CompilerServices.Unsafe'.
06-21 09:58:18.970 F/monodroid-assembly( 3632): Could not load assembly 'System.Runtime.CompilerServices.Unsafe' during startup registration.
06-21 09:58:18.970 F/monodroid-assembly( 3632): This might be due to an invalid debug installation.

I then tried to add the ‘System.Runtime.CompilerServices.Unsafe’ NuGet package manually to my project, but it didnt fix the problem. I messed around a lot, trying different build parameters and such and actually got the app running on an Android 7 emulator. However, after a project clean and rebuild, the error showed up again.

Any help on how to get EFCore Sqlite to work on Android 7?

Steps to reproduce

Sample project: https://github.com/tipa/EFCoreSample (Basically just the basic Android template from VS + the Nuget preview package)

Further technical details

EF Core version: v2.0.0-preview1-final Database Provider: Microsoft.EntityFrameworkCore.Sqlite Xamarin: 4.5.0.486 Xamarin.Android: 7.3.1.2 Operating system: Windows 10 IDE: Visual Studio 2017 15.2

About this issue

Original URL
State: closed
Created 7 years ago
Reactions: 5
Comments: 41 (5 by maintainers)

Most upvoted comments

@alexdrl

use package.config and do a Clean Build or
if you’re using PackageReference, make sure you’ve manually added System.Runtime.CompilerServices.Unsafe 4.3.0 nuget package and do a Clean Build (delete obj/bin folders, restore nuget packages etc)

erikpowa on Nov 17, 2017

Thanks @bricelam. I started an email thread with the Xamarin folks to figure out with them how to best manage this and other issues that were reported here but appear to be Xamarin issues.

At least for now, I would like to make sure such issues are also marked <kbd>area-external</kbd> to distinguish them from any Xamarin-related issues we need to address on our side. Can you please help me make sure they are?

divega on Dec 12, 2017

I investigated this a little. It seems like Microsoft.Extensions.Primitives has a dependency on System.Runtime.CompilerServices.Unsafe. When the Linker runs, it looks for the DLL in the directory of Microsoft.Extensions.Primitives, which is not downloaded by NuGet.

I have downloaded the NuGet Package System.Runtime.CompilerServices.Unsafe 4.4.0, extracted the DLL and linked it with a normal Reference. This way it will be copied into the output directories and can be linked.

This is my previous workaround:

@alexdrl I think the following trick is necessary to make it work.

Manually edit the csproj file of your project and define, that the NU1605 warning shouldn’t be treated as an error:

<PropertyGroup>
  <NoWarn>$(NoWarn);NU1605</NoWarn>
</PropertyGroup>

Then in your Project File add the System.Runtime.CompilerServices.Unsafe Package in Version 4.3.0 as mentioned by @erikpowa:

<PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.3.0" />

Then I would:

Remove the App from the Device / Simulator
Clean the NuGet Caches
Clean all bin and obj folders
Restore the Packages
Build

After a successful build your Xamarin App should start with Entity Framework 2.0. 👍

bytefish on Jan 5, 2018

@bytefish @erikpowa That workaround worked good… as we’re working closely to the latest version of .NET Core/Standard and Xamarin, could you give us some explanation of why is this happening?

Thank you for the workaround.

Also, as we have found with other package version mismatch, this package downgrade workaround breaks the assemblies linking.

alexdrl on Nov 20, 2017

@divega Can we follow up with the Xamarin Android team on this?

bricelam on Dec 11, 2017

We’re having the same issue using EF Core 2.0.1 in VS 15.4.3 and VS 15.5 Preview 3 with no luck.

This is annoying because the Xamarin application is now blocked because of this.

alexdrl on Nov 17, 2017

ah right. that one is also an important one 😃 Glad it worked 😃

NPadrutt on Sep 4, 2017