Upgrading to .NET6 breaks unit tests which launch 32-bit .NET processes #22647
Description
Tests which launch 32-bit .NET processes fail after upgrading to .NET6 when run from the CLI (running via VS works fine). The 32-bit exe fails to launch with:
The library hostfxr.dll was found, but loading it from C:\Program Files\dotnet\host\fxr\6.0.0\hostfxr.dll failed
- Installing .NET prerequisites might help resolve this problem.
https://go.microsoft.com/fwlink/?linkid=798306
The issue does not occur when using .NET5 or when running the test via the VS test explorer.
The issue has been reported on the NUnit3TestAdapter repo since, but apparently the adapter is in play even when running via the VS test explorer (suggesting that the issue may lie elsewhere). Issue: nunit/nunit3-vs-adapter#917
Here's a repo with a minimal reproducible example and a COREHOST trace file: https://github.com/handerss-tibco/net6-nunit-32bit-fail
Here's the trace file: https://github.com/handerss-tibco/net6-nunit-32bit-fail/blob/main/trace.txt
The trace file indicates that the runtime identifier is being set to 64-bit before launch of the 32-bit exe:
Property NATIVE_DLL_SEARCH_DIRECTORIES = C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.0\;
Property PLATFORM_RESOURCE_ROOTS = C:\Source\TestProcess32\UnitTest\bin\Debug\net6.0\;
Property APP_CONTEXT_BASE_DIRECTORY = C:\Source\TestProcess32\UnitTest\bin\Debug\net6.0\
Property APP_CONTEXT_DEPS_FILES = C:\Source\TestProcess32\UnitTest\bin\Debug\net6.0\UnitTest.deps.json;C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.0\Microsoft.NETCore.App.deps.json
Property PROBING_DIRECTORIES =
Property RUNTIME_IDENTIFIER = win10-x64
Property System.Reflection.Metadata.MetadataUpdater.IsSupported = false
CoreCLR path = 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.0\coreclr.dll', CoreCLR dir = 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.0\'
Loaded library from C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.0\coreclr.dll
Launch host: C:\Source\TestProcess32\UnitTest\bin\Debug\net6.0\testhost.exe, app: C:\Source\TestProcess32\UnitTest\bin\Debug\net6.0\testhost.dll, argc: 10, args: --port,61918,--endpoint,127.0.0.1:061918,--role,client,--parentprocessid,127200,--telemetryoptedin,false,
--- Begin breadcrumb write
Breadcrumbs will be written using a background thread
Breadcrumb thread write callback...
--- End breadcrumb write 1
Tracing enabled @ Tue Nov 16 14:00:45 2021 GMT
--- Invoked apphost [version: 6.0.0, commit hash: 4822e3c3aa77eb82b2fb33c9321f923cf11ddde6] main = {
TestProcess32.exe
}
Redirecting errors to custom writer.
The managed DLL bound to this executable is: 'TestProcess32.dll'
Using environment variable DOTNET_ROOT=[C:\Program Files\dotnet] as runtime location.
Reading fx resolver directory=[C:\Program Files\dotnet\host\fxr]
Considering fxr version=[2.1.30]...
Considering fxr version=[5.0.12]...
Considering fxr version=[6.0.0]...
Detected latest fxr version=[C:\Program Files\dotnet\host\fxr\6.0.0]...
Resolved fxr [C:\Program Files\dotnet\host\fxr\6.0.0\hostfxr.dll]...
Failed to load the dll from [C:\Program Files\dotnet\host\fxr\6.0.0\hostfxr.dll], HRESULT: 0x800700C1
The library hostfxr.dll was found, but loading it from C:\Program Files\dotnet\host\fxr\6.0.0\hostfxr.dll failed
- Installing .NET prerequisites might help resolve this problem.
https://go.microsoft.com/fwlink/?linkid=798306
Versions:
.NET SDK: 6.0.100
Microsoft.NET.Test.Sdk 17.0.0
NUnit 3.13.2
NUnit3TestAdapter: 4.1.0