"Native linking failed, undefined symbol ..." when building in debug mode

[MichaelRumpler]

I finally managed to reproduce the errors reported in issue #10884. I couldn't reproduce it in a new project so I had to take my actual app and remove code until it was almost empty. The difference is, that I already get those linker errors when building in debug mode. The linker should not get involved at all in this stage.

Steps to Reproduce

1. Open the attached repro project in VS for Windows
2. Set the iOS project as startup project
3. Pair to a Mac
4. Build the iOS project

Expected Behavior

It builds successfully.

Actual Behavior

The build fails with "Native linking failed, undefined symbol ...". The missing symbols sound very Windows specific.

C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _AllocateLocallyUniqueId. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _CheckTokenMembership. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _CloseHandle. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _ConvertStringSidToSidW. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _CreateWellKnownSid. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _DuplicateHandle. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _DuplicateTokenEx. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
C:\Program Files\Microsoft Visual Studio\2022\Preview\MSBuild\Xamarin\iOS\Xamarin.iOS.Common.targets(224,3): error MT5210: Native linking failed, undefined symbol: _EqualDomainSid. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.

If I don't pair VS to a Mac and only build locally on Windows, then it works.

Environment

VS 17.5.0 Preview 2 + 3 with Xamarin.iOS 16.1.1.28, Xcode 14.1 and macOS 13.0.1
(I also updated to VS Preview 4, which wanted to install Xamarin.iOS 16.2.0.2 which refrains working with Xcode 14.1. Xcode 14.2 is downloading now.)

Example Project (If Possible)

In the shared project RoyalLogging somebody added a reference to System.Diagnostics.EventLog and uses classes like System.Diagnostics.EventLog. This makes no sense on iOS, but as it is a netstandard2.0 dll, it is totally possible. The code is in the file WindowsEventLogLogger.cs. I don't use that class anywhere in my solution. It is only used on Windows.

I also left a reference to Microsoft.AppCenter.Analytics in the repro. If I remove it, then it raises a different error and I was not sure, if it was still the same as in #10884.

Repro_NativeLinker.zip

[MichaelRumpler]

All the updates finished now. The same still happens with
VS 17.5.0 Preview 4, Xamarin.iOS 16.2.0.2, Xcode 14.2 and macOS 13.2.

[rolfbjarne]

Could you get a binary build log as explained here: https://github.com/xamarin/xamarin-macios/wiki/Diagnosis#binary-build-logs? Thanks!

[ghost]

Hi @MichaelRumpler. We have added the "need-info" label to this issue, which indicates that we have an open question for you before we can take further action. This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[MichaelRumpler]

msbuild with just /bl is not enough, because it builds without Mac and thus succeeds.

I tried set MSBuildDebugEngine=1. The build is taking 30mins now. Usually I'd say it hung, but maybe it does take that long with all the debugging on. I now have to leave. Will upload that stuff when I'm back (maybe after retrying).

But you do have a repro project. So you should be able to create all the logs you need yourself.

[MichaelRumpler]

It did hang yesterday. Today I restarted VS and reproduced it after building for 2mins.
MSBuild_Logs.zip

[rolfbjarne]

This is a rather interesting and complex problem.

Just for reference: the error shows up in the file CentralNode_devenv_PID=21140_x64_BuildManager_Default_3.binlog in the attached zip above.
Here's a working binlog from a build on macOS: msbuild.binlog.zip

What I figured out:

The reason it fails, is because the Windows build references the netstandard1.3 version of System.Security.Principal.Windows.dll:

C:\Users\micha.nuget\packages\system.security.principal.windows\5.0.0\runtimes\win\lib\netstandard1.3\System.Security.Principal.Windows.dll

while in the Mac build we don't get the reference directly, instead the version shipped with Xamarin.iOS is loaded because:

[...]
Loaded assembly 'System.Diagnostics.EventLog, Version=7.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' from /Users/rolf/.nuget/packages/system.diagnostics.eventlog/7.0.0/lib/netstandard2.0/System.Diagnostics.EventLog.dll
    References: 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'
    References: 'System.Security.Principal.Windows, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
Loaded assembly 'System.Security.Principal.Windows, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' from /Users/rolf/work/maccore/msbuild/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/lib/mono/Xamarin.iOS/Facades/System.Security.Principal.Windows.dll
    References: 'mscorlib, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e'
[...]

It's not entirely clear from the build log the reason for this difference in behavior, but it seems the _HandlePackageFileConflicts target returns different results between Mac and Windows, on Mac it finds a conflict with the System.Security.Principal.Windows.dll assembly, and stops using this assembly in the later parts of the build.

I could spend time diagnosing more, but since this is a legacy Xamarin.iOS project, it's unlikely we'll spend time fixing the issue on our end, in particular because it's likely this is fixed in .NET anyways (note that the System.Diagnostics.EventLog package does not depend on System.Security.Principal.Windows in .NET 6+: https://www.nuget.org/packages/System.Diagnostics.EventLog#dependencies-body-tab).

However, I have an idea for a workaround: explicitly reference System.Security.Principal.Windows, and maybe that will make us resolve the correct reference:

diff --git a/RoyalMobileApps.XF.iOS/RoyalMobileApps.XF.iOS.csproj b/RoyalMobileApps.XF.iOS/RoyalMobileApps.XF.iOS.csproj
index 25d8644..bdb5f66 100644
--- a/RoyalMobileApps.XF.iOS/RoyalMobileApps.XF.iOS.csproj
+++ b/RoyalMobileApps.XF.iOS/RoyalMobileApps.XF.iOS.csproj
@@ -166,6 +166,7 @@
     <Reference Include="System.Net.Http" />
     <Reference Include="System.Xml" />
     <Reference Include="System.Core" />
+    <Reference Include="System.Security.Principal.Windows" />^M
     <Reference Include="Xamarin.iOS">
       <Private>False</Private>
     </Reference>

Can you try that and see if it works?

Another potential workaround is to remove the System.Diagnostics.EventLog package reference, if that's something you can do without.

[ghost]

Hi @MichaelRumpler. We have added the "need-info" label to this issue, which indicates that we have an open question for you before we can take further action. This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[MichaelRumpler]

Nope, that doesn't seem to work. It's still the same error.

However, we removed that class and the NuGet reference from the shared project and added it in the Windows app instead. This does the trick.

I mainly wanted it to be documented. Maybe you could add a link in the original issue #10884. It doesn't display the reference automatically. Maybe because it's locked.

[rolfbjarne]

I mainly wanted it to be documented. Maybe you could add a link in the original issue #10884. It doesn't display the reference automatically. Maybe because it's locked.

I've added a comment on that issue.