NativeAOT seems to export function names in a weird format (ExportedName = Namespace_Namespace_DllMain__ExportedName)

[SparkyTD]

I'm trying to write a UDF for a very old Firebird 2.1.5 database server. I'm testing the UDF with the following function:

[UnmanagedCallersOnly(EntryPoint = nameof(TestUdf), CallConvs = new[] { typeof(CallConvCdecl) })]
public static unsafe int TestUdf(int* input)
{
    return *input * 2;
}

And publishing the native DLL with this command:

dotnet publish -c Release -r win-x64 -p:NativeLib=Shared -p:PublishAot=true

However when I try to load the function from Firebird, it fails to find the entry point.

If I investigate the generated function with the dumpbin /exports command, it shows that the exported function names aren't exactly formatted as they should be:

ordinal hint RVA      name

          1    0 00326060 DotNetRuntimeDebugHeader = DotNetRuntimeDebugHeader
          3    2 0008B9D0 TestUdf = FirebirdUdf_FirebirdUdf_DllMain__TestUdf

I've never seen this weird 'ExportedName = Namespace_Namespace_DllMain__ExportedName' notation, and I believe this is what's causing the issues. It's important to note that I tested the same UDF shortly after .NET 7 was released, on the same Firebird database, and it worked without any issues. I also don't remember seeing this weird exported name format back then. Maybe something was changed in a more recent .NET 7 update? Is there a way to ensure that the exported names appear exactly like they're specified in the C# code, without the '=' sign?

[jkotas]

The exported name is TestUdf (ie it is the name to pass to GetProcAddress Windows API). FirebirdUdf_FirebirdUdf_DllMain__TestUdf is internal symbol name create by native AOT name mangler, it is not the exported name.