Clang++ exited with code 1 - Duplicate Symbols

[vouksh]

I'm encountering an issue while trying to build a project that's referencing a native binding library.
The binding project was created with .NET 7, and builds an runs with a .NET 7 project. However, in a .NET 8 project, the build fails due to "duplicate symbols" and "duplicate libraries"

I have verified that the library does not contain duplicate symbols using the method from Xamarin.iOS Errors
Here is the fgrep output for one of the symbols the log says is duplicated:

jackaardal@*** BlueRadioBrsp64 % nm lib_brsp_1.3.1.arm64.a | fgrep '_isDataModeSupported'
000000000000c9a8 S _OBJC_IVAR_$_Brsp._isDataModeSupported
jackaardal@*** BlueRadioBrsp64 %

The output is reporting that literally every symbol in the library is a duplicate.
It seems like it's trying to link from both the local path on my Windows laptop and from the remote path on the MacBook, as it's listed twice in the clang++ arguments.

I've tried multiple solutions presented in various other issues, and nothing changes.

Steps to Reproduce

1. Create an iOS binding library
2. Set the native reference to Static, don't enable SmartLink, and enable ForceLoad
3. Reference binding project from .NET 8.0 RC2 MAUI app
4. Pair to a MacBook from Windows
5. Attempt to build.

Expected Behavior

App builds and is able to utilize native library

Actual Behavior

Build fails with false duplicate symbol errors.

duplicate symbol '_OBJC_IVAR_$_Brsp._serviceDiscoveryCount' in:
    D:/Nuget/blueradiobrsp64/1.1.0-preview1017/lib/net7.0-ios16.1/BlueRadioBrsp64.resources/lib_brsp_1.3.1.a(Brsp.o)
    /Users/jackaardal/Library/Caches/Xamarin/mtbs/builds/KinesiaOne/7669fae6a0e78117d3638e4eb3145c6038ab08ffdc3d331766a0d10d73a8f661/D:/Nuget/blueradiobrsp64/1.1.0-preview1017/lib/net7.0-ios16.1/BlueRadioBrsp64.resources/lib_brsp_1.3.1.a(Brsp.o)

Environment

Windows Development Environment

[System Summary]

Item	Value	
OS Name	Microsoft Windows 11 Business	
Version	10.0.22621 Build 22621	
Other OS Description 	Not Available	
OS Manufacturer	Microsoft Corporation	
System Name	***
System Manufacturer	Dell Inc.	
System Model	Precision 7550	
System Type	x64-based PC	
System SKU	09C3	
Processor	Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz, 2592 Mhz, 6 Core(s), 12 Logical Processor(s)	
BIOS Version/Date	Dell Inc. 1.21.0, 2/13/2023	
SMBIOS Version	3.2	
Embedded Controller Version	255.255	
BIOS Mode	UEFI	
BaseBoard Manufacturer	Dell Inc.	
BaseBoard Product	04JGVR	
BaseBoard Version	A01	
Platform Role	Mobile	
Secure Boot State	On	
PCR7 Configuration	Elevation Required to View	
Windows Directory	C:\WINDOWS	
System Directory	C:\WINDOWS\system32	
Boot Device	\Device\HarddiskVolume1	
Locale	United States	
Hardware Abstraction Layer	Version = "10.0.22621.1413"	
User Name	***
Time Zone	Eastern Daylight Time	
Installed Physical Memory (RAM)	32.0 GB	
Total Physical Memory	31.6 GB	
Available Physical Memory	13.4 GB	
Total Virtual Memory	63.6 GB	
Available Virtual Memory	36.1 GB	

MacOS Development Environment

Model: MacBook Pro 17
CPU: Apple M1
RAM: 16GB
OS: macOS Sonoma 14.1

Version information

Microsoft Visual Studio Community 2022
Version 17.8.0 Preview 5.0
VisualStudio.17.Preview/17.8.0-pre.5.0+34219.65
Microsoft .NET Framework
Version 4.8.09032

Installed Version: Community

Visual C++ 2022   00482-90000-00000-AA965
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Xamarin Designer   17.8.3.6 (remotes/origin/d17-8@eccf46a291)
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Xamarin Templates   17.8.16 (830b56a)
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Xamarin.Android SDK   13.2.2.0 (d17-5/45b0e14)
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    Mono: d9a6e87
    Java.Interop: xamarin/java.interop/d17-5@149d70fe
    SQLite: xamarin/sqlite/3.40.1@68c69d8
    Xamarin.Android Tools: xamarin/xamarin-android-tools/d17-5@ca1552d


Xamarin.iOS and Xamarin.Mac SDK   16.4.0.18 (9d266025e)
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.

Build Logs

msbuild-asnuget.zip
msbuild-asproject.zip

Example Project (If Possible)

I'm unable to provide an example project, as the library is proprietary, and we don't have permission to share it.

[rolfbjarne]

Would you be able to share the BlueRadioBrsp64 NuGet (.nupkg file) with us?

[vouksh]

@rolfbjarne Do you have a way I can send it directly to you? I am not allowed to share it publicly, but I have permission to send it to you for support. It's a binding library to communicate with a proprietary Bluetooth sensor.

[rolfbjarne]

I am not allowed to share it publicly, but I have permission to send it to you for support.

If you create a new feedback ticket here: https://developercommunity.visualstudio.com/VisualStudioMac/report, you can add private attachments afterwards. Explain in the ticket that you're just adding private information to this issue, and post a link here to the feedback ticket so I can link them up.

[vouksh]

Submitted and attached the files.
As a bit of extra background, this library has worked previously. I'm in the process of rewriting one of our Xamarin.iOS native apps into MAUI. It is currently working in production with no issues, and the duplicate symbol errors seem to be unique to .NET 8.

Here's the link to the ticket: https://developercommunity.visualstudio.com/t/Clang-exited-with-code-1---Duplicate-S/10506451

[rolfbjarne]

Can you try adding setting CompressBindingResourcePackage=true in the binding project to see if that makes it work?

<PropertyGroup>
    <CompressBindingResourcePackage>true</CompressBindingResourcePackage>
</PropertyGroup>

[vouksh]

That allows me to build, but now when accessing the library the app crashes.

11:42:20:081	=================================================================
11:42:20:081		Native Crash Reporting
11:42:20:081	=================================================================
11:42:20:081	Got a SIGABRT while executing native code. This usually indicates
11:42:20:081	a fatal error in the mono runtime or one of the native libraries 
11:42:20:081	used by your application.
11:42:20:081	=================================================================
11:42:20:081	
11:42:20:081	=================================================================
11:42:20:081		Native stacktrace:
11:42:20:081	=================================================================
11:42:20:081	
11:42:20:874	The app has been terminated.
11:42:20:874	1f31173d8  c0 03 5f d6 d0 03 80 d2 01 10 00 d4 03 01 00 54  .._............T
11:42:20:874	
11:42:20:874		0x10050a95c - /private/var/containers/Bundle/Application/78603BED-58BD-4DD4-968D-37507F8C5307/KinesiaOne.app/KinesiaOne : AppleCryptoNative_X509ImportCollection
11:42:20:874		0x1004f2384 - /private/var/containers/Bundle/Application/78603BED-58BD-4DD4-968D-37507F8C5307/KinesiaOne.app/KinesiaOne : AppleCryptoNative_X509ImportCollection
11:42:20:874		0x1006450a4 - /private/var/containers/Bundle/Application/78603BED-58BD-4DD4-968D-37507F8C5307/KinesiaOne.app/KinesiaOne : AppleCryptoNative_X509ImportCollection
11:42:20:874		0x10050a14c - /private/var/containers/Bundle/Application/78603BED-58BD-4DD4-968D-37507F8C5307/KinesiaOne.app/KinesiaOne : AppleCryptoNative_X509ImportCollection
11:42:20:874		0x215611888 - /usr/lib/system/libsystem_platform.dylib : <redacted>
11:42:20:874		0x1f313dee0 - /usr/lib/system/libsystem_kernel.dylib : <redacted>
11:42:20:874		0x1f313df14 - /usr/lib/system/libsystem_kernel.dylib : 
11:42:20:874		0x1cc7d7910 - /System/Library/PrivateFrameworks/TCC.framework/TCC : <redacted>
11:42:20:874		0x1cc7d3ebc - /System/Library/PrivateFrameworks/TCC.framework/TCC : <redacted>
11:42:20:874		0x1cc7db210 - /System/
11:42:20:874	Library/PrivateFrameworks/TCC.framework/TCC : <redacted>
11:42:20:874		0x215716b44 - /usr/lib/system/libxpc.dylib : <redacted>
11:42:20:874		0x2157094b4 - /usr/lib/system/libxpc.dylib : <redacted>
11:42:20:874		0x1b445b380 - /usr/lib/system/libdispatch.dylib : <redacted>
11:42:20:874		0x1b4478b04 - /usr/lib/system/libdispatch.dylib : <redacted>
11:42:20:874		0x1b446dd40 - /usr/lib/system/libdispatch.dylib : <redacted>
11:42:20:874		0x1b446d628 - /usr/lib/system/libdispatch.dylib : <redacted>
11:42:20:874		0x2156b699c - /usr/lib/system/libsystem_pthread.dylib : _pthread_wqthread
11:42:20:874		0x2156b6a04 - /usr/lib/system/libsystem_pthread.dylib : start_wqthread
11:42:20:874	
11:42:20:874	=================================================================
11:42:20:874		Basic Fault Address Reporting
11:42:20:874	=================================================================
11:42:20:874	Memory around native instruction pointer (0x1f31173b8):0x1f31173a8  ff 0f 5f d6 c0 03 5f d6 30 41 80 d2 01 10 00 d4  .._..._.0A......
11:42:20:874	0x1f31173b8  03 01 00 54 7f 23 03 d5 fd 7b bf a9 fd 03 00 91  ...T.#...{......
11:42:20:874	0x1f31173c8  01 d5 ff 97 bf 03 00 91 fd 7b c1 a8 ff 0f 5f d6  .........{...._.
11:42:20:874	0x

When looking back through the build logs, I now see this warning:

6>C:\Program Files\dotnet\packs\Microsoft.iOS.Windows.Sdk\17.0.8465-net8-rc2.1\tools\msbuild\iOS\Xamarin.iOS.Common.After.targets(364,3): warning MT1308: Could not extract the native library 'lib_brsp_1.3.1.a' from the assembly '/Users/jackaardal/Library/Caches/Xamarin/mtbs/builds/KinesiaOne/7669fae6a0e78117d3638e4eb3145c6038ab08ffdc3d331766a0d10d73a8f661/D:/repos/KinesiaOne-Maui/DeviceAPIs/BlueRadioBrsp64/bin/Debug/net8.0-ios/BlueRadioBrsp64.dll', because it doesn't contain the resource 'lib_brsp_1.3.1.a'.

[rolfbjarne]

/System/Library/PrivateFrameworks/TCC.framework/TCC :

That looks like a missing entry in your Info.plist for some feature iOS will show a permission dialog about.

You should get a somewhat better crash report if you disable stripping in your csproj:

<PropertyGroup>
    <NoSymbolStrip>true</NoSymbolStrip>
</PropertyGroup>

that might reveal a bit more.