Could not find a suitable hostfxr library

[gabloe]

Environment

• Pythonnet version: 3.0.0.post1
• Python version: 3.8
• Operating System: macOS 12.6
• .NET Runtime: .NETCore 6
• Architecture: arm64 (Apple M1)

Details

import os
import sys
from clr_loader import get_coreclr
from pythonnet import set_runtime

runtime_config = os.path.join("/Users/gabloe/dotnetconfig", "pythonnettest.runtimeconfig.json")
rt = get_coreclr(runtime_config=runtime_config)
set_runtime(rt)

import clr

Traceback

Traceback (most recent call last):
...
    rt = get_coreclr(runtime_config=runtime_config)
  File "/Users/gabloe/Library/Caches/pypoetry/virtualenvs/test-lQu4lGUY-py3.8/lib/python3.8/site-packages/clr_loader/__init__.py", line 122, in get_coreclr
    impl = DotnetCoreRuntime(runtime_config=runtime_config, dotnet_root=dotnet_root)
  File "/Users/gabloe/Library/Caches/pypoetry/virtualenvs/test-lQu4lGUY-py3.8/lib/python3.8/site-packages/clr_loader/hostfxr.py", line 20, in __init__
    self._dll = load_hostfxr(self._dotnet_root)
  File "/Users/gabloe/Library/Caches/pypoetry/virtualenvs/test-lQu4lGUY-py3.8/lib/python3.8/site-packages/clr_loader/ffi/__init__.py", line 31, in load_hostfxr
    raise RuntimeError(f"Could not find a suitable hostfxr library in {dotnet_root}")
RuntimeError: Could not find a suitable hostfxr library in /usr/local/share/dotnet
Exception ignored in: <function Runtime.__del__ at 0x7f8609306820>
Traceback (most recent call last):
  File "/Users/gabloe/Library/Caches/pypoetry/virtualenvs/test-lQu4lGUY-py3.8/lib/python3.8/site-packages/clr_loader/types.py", line 137, in __del__
    self.shutdown()
  File "/Users/gabloe/Library/Caches/pypoetry/virtualenvs/test-lQu4lGUY-py3.8/lib/python3.8/site-packages/clr_loader/hostfxr.py", line 111, in shutdown
    if self._handle is not None:
AttributeError: 'DotnetCoreRuntime' object has no attribute '_handle'

[filmor]

I don't have a mac to check this, but could it be that the issue is along the lines of #36, that the dotnet path is not looked up correctly? What's the output of which dotnet in a terminal?

[gabloe]

I don't have a mac to check this, but could it be that the issue is along the lines of #36, that the dotnet path is not looked up correctly? What's the output of which dotnet in a terminal?

gabloe ~> which dotnet
/usr/local/share/dotnet/dotnet

Seems to be correct, at least it is the same path referenced in the exception

[gabloe]

Also if it helps, here is the .NET information from my system:

 gabloe /usr/local/share/dotnet> dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.402
 Commit:    6862418796

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  12.6
 OS Platform: Darwin
 RID:         osx.12-arm64
 Base Path:   /usr/local/share/dotnet/sdk/6.0.402/

global.json file:
  Not found

Host:
  Version:      6.0.10
  Architecture: arm64
  Commit:       5a400c212a

.NET SDKs installed:
  6.0.302 [/usr/local/share/dotnet/sdk]
  6.0.401 [/usr/local/share/dotnet/sdk]
  6.0.402 [/usr/local/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 6.0.7 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.9 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.10 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.7 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.9 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.10 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]

Download .NET:
  https://aka.ms/dotnet-download

Learn about .NET Runtimes and SDKs:
  https://aka.ms/dotnet/runtimes-sdk-info

[gabloe]

Also, a screenshot of my /usr/local/share/dotnet directory struture, showing libhostfxr:

[gabloe]

After stepping through this with debugger, it seems to be a machine architecture mismatch.

"cannot load library '/usr/local/share/dotnet/host/fxr/6.0.9/libhostfxr.dylib': dlopen(/usr/local/share/dotnet/host/fxr/6.0.9/libhostfxr.dylib, 0x0002): tried: '/usr/local/share/dotnet/host/fxr/6.0.9/libhostfxr.dylib' (mach-o file, but is an incompatible architecture (have (arm64), need (x86_64)))"

But I am unsure why it is expecting x86_64 here.

[filmor]

Because your Python is x86-64. The architectures have to match.

[gabloe]

Ahh, that is right. After re-installing python from the universal package it is now working properly. Thanks @filmor.

[thomasnal]

It makes sense and gives me the insight. Thanks.

In my case, I have python architecture arm64, .net architecture arm64, but the host/fxr folder has only these versions:

$ ls -l /usr/local/share/dotnet/x64/host/fxr/
total 0
drwxr-xr-x  3 root  wheel  96 16 Jun 00:09 3.1.27
drwxr-xr-x  3 root  wheel  96 26 Sep 21:30 3.1.30

I need to find out how to make dotnet install hostfxr 6.10.

EDITED: because of the /usr/local/share/dotnet/x64. The arm64e is in /usr/local/share/dotnet/host. Why pythonnet looks for x86 when in the case of mono it looks for arm64e? My Python is arm64 version.

[thomasnal]

I copied dotnet/host/fxr/6.0.10 to dotnet/x64/host/fxr leading to this error,

You must install or update .NET to run this application.

App: /Users/thomasnal/.pyenv/versions/3.9.13/bin/python3.9
Architecture: arm64
Framework: 'Microsoft.NETCore.App', version '6.0.10' (arm64)
.NET location: /usr/local/share/dotnet/x64

The following frameworks were found:
  3.1.27 at [/usr/local/share/dotnet/x64/shared/Microsoft.NETCore.App]
  3.1.30 at [/usr/local/share/dotnet/x64/shared/Microsoft.NETCore.App]

How can I tell to pythonnet that the correct dotnet path /usr/local/share/dotnet (without x64)?

@filmor can you advise?

[thomasnal]

When I override the dotnet path that pythonnet uses then runtime loads up,

from pythonnet import set_runtime
from clr_loader import get_coreclr

rt = get_coreclr(dotnet_root=Path('/usr/local/share/dotnet'))
set_runtime(rt)

import clr

[filmor]

The lookup code is contained in https://github.com/pythonnet/clr-loader/blob/master/clr_loader/util/find.py, PRs are welcome. I don't have a Mac (and don't plan on getting one anytime soon), so I can't test this behaviour. It looks to me like this previous PR is the culprit: #37

It adjusted the lookup logic to find the dotnet root for 64bit macOS, but it didn't take the architecture into account.

[LeeDongGeon1996]

@filmor Sorry, I also think my previous PR is wrong..
To check system architecture correctly, we need the codes below:

if "ARM" in platform.machine().upper():

If you don't mind, can I send fixed PR?

[zarkin404]

When I override the dotnet path that pythonnet uses then runtime loads up,

from pythonnet import set_runtime
from clr_loader import get_coreclr

rt = get_coreclr(dotnet_root=Path('/usr/local/share/dotnet'))
set_runtime(rt)

import clr

dude, you save my time