[release/7.0.2xx] [tests] Find a workaround for #xamarin/maccore@2668. #18178
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1. Mono changed dyld lookup to start looking in directories in NATIVE_DLL_SEARCH_DIRECTORIES before the actual given path, even when the given path is absolute [1]. 2. This turned out to break Mac Catalyst, because when a DllImport says a P/Invoke is in "/System/Library/Frameworks/SceneKit.framework/SceneKit", Mono would try loading by prefixing the directories in NATIVE_DLL_SEARCH_DIRECTORIES. We add the Contents/MonoBundle directory to NATIVE_DLL_SEARCH_DIRECTORIES, so Mono would try to load "/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit", and things would go wrong. 3. We found a workaround: add "/" to NATIVE_DLL_SEARCH_DIRECTORIES. This works on Ventura, but apparently not on older macOS version, because the actual path we pass to dlopen ends up being "///System/Library/Frameworks/SceneKit.framework/SceneKit" (note the three initial slashes instead of a single slash). 4. Add a second workaround, where we add a dll import resolver to load exactly the path we want to load. [1]: dotnet/runtime@5a1baeb [2]: dotnet/runtime#85255 Technical sidenote: Why trying to load "/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit" turned out so bad on Mac Catalyst is not obvious. What happens is this: * The app calls 'dlopen ("/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit")' * dlopen checks if this is a Mac Catalyst override of a macOS system framework, by prefixing "/System/iOSSupport" and trying to load that. So dlopen would try to load "/System/iOSSupport/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit", which would obviously fail. * Then dlopen would try a few more fallbacks, eventually trying "/System/Library/Frameworks/SceneKit.framework/SceneKit", and successfully loading that library. * Unfortunately "/System/Library/Frameworks/SceneKit.framework/SceneKit" is the wrong library to load for Mac Catalyst ("/System/iOSSupport/System/Library/Frameworks/SceneKit.framework/SceneKit" is the correct version). These two libraries are incompatible, and calling one when you mean to call the other will do nasty things like corrupting the stack. This is a backport of xamarin#18159.
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❌ [PR Build] Tests on macOS M1 - Mac Big Sur (11.5) failed ❌Failed tests are:
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❌ [PR Build] Tests on macOS M1 - Mac Ventura (13.0) failed ❌Failed tests are:
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🔥 [CI Build] Test results 🔥Test results❌ Tests failed on VSTS: simulator tests 0 tests crashed, 4 tests failed, 73 tests passed. Failures❌ monotouch tests
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Test failures are unrelated (https://github.com/xamarin/maccore/issues/2197). |
NATIVE_DLL_SEARCH_DIRECTORIES before the actual given path, even when the
given path is absolute 1.
P/Invoke is in "/System/Library/Frameworks/SceneKit.framework/SceneKit",
Mono would try loading by prefixing the directories in
NATIVE_DLL_SEARCH_DIRECTORIES. We add the Contents/MonoBundle directory to
NATIVE_DLL_SEARCH_DIRECTORIES, so Mono would try to load
"/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit",
and things would go wrong.
on Ventura, but apparently not on older macOS version, because the actual
path we pass to dlopen ends up being "///System/Library/Frameworks/SceneKit.framework/SceneKit"
(note the three initial slashes instead of a single slash).
the path we want to load.
Technical sidenote:
Why trying to load "/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit"
turned out so bad on Mac Catalyst is not obvious. What happens is this:
framework, by prefixing "/System/iOSSupport" and trying to load that. So
dlopen would try to load "/System/iOSSupport/path/to/my.app/Contents/MonoBundle//System/Library/Frameworks/SceneKit.framework/SceneKit",
which would obviously fail.
"/System/Library/Frameworks/SceneKit.framework/SceneKit", and successfully
loading that library.
the wrong library to load for Mac Catalyst ("/System/iOSSupport/System/Library/Frameworks/SceneKit.framework/SceneKit"
is the correct version). These two libraries are incompatible, and calling
one when you mean to call the other will do nasty things like corrupting the
stack.
This is a backport of #18159.