Remove explicit WinRT initialization/uninitialization - #122940
#122940Merged
jkotas merged 5 commits intoJan 7, 2026
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Remove explicit WinRT initialization/uninitialization#122940jkotas merged 5 commits intomaindotnet/runtime:mainfrom copilot/remove-explicit-winrt-initializationdotnet/runtime:copilot/remove-explicit-winrt-initializationCopy head branch name to clipboard
jkotas merged 5 commits into
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- Remove TSNC_WinRTInitialized flag from threads.h - Remove IsWinRTInitialized() and ResetWinRTInitialized() methods - Remove BaseWinRTUninitialize() method declaration and implementation - Remove all RoInitialize/RoUninitialize calls from CoreCLR - Remove ENABLE_WINRT conditional compilation from NativeAOT - Remove RuntimeObject.lib from all CMakeLists.txt files Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>
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changed the title
[WIP] Remove explicit WinRT initialization and related components
Remove explicit WinRT initialization/uninitialization
Jan 6, 2026
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@copilot FIx build break D:\a_work\1\s\src\coreclr\vm\threads.cpp(3724): error C3861: 'IsWinRTInitialized': identifier not found |
jkotas
reviewed
Jan 6, 2026
jkotas
reviewed
Jan 6, 2026
Removed the remaining reference to IsWinRTInitialized() at line 3724 in threads.cpp that was causing the build break. Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>
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Author
Removed redundant IsCoInitialized() checks that were performed both before and inside the conditional blocks. Applied the same simplification in three locations in threads.cpp as requested in code review. Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>
jkotas
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Jan 6, 2026
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Tagging subscribers to this area: @dotnet/interop-contrib |
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Pull request overview
This PR removes redundant WinRT-specific initialization code from the runtime, consolidating all COM/WinRT interop to use standard COM initialization via CoInitializeEx/CoUninitialize.
Key Changes:
- Removed
TSNC_WinRTInitializedthread state flag and all WinRT-specific initialization/cleanup methods from CoreCLR - Eliminated
ENABLE_WINRTconditional compilation from NativeAOT, standardizing onCoInitializeEx - Removed
RuntimeObject.libdependency from all build configurations
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
| src/coreclr/vm/threads.h | Removed TSNC_WinRTInitialized flag and WinRT-specific methods (IsWinRTInitialized, ResetWinRTInitialized, BaseWinRTUninitialize) |
| src/coreclr/vm/threads.cpp | Removed BaseWinRTUninitialize() implementation and all RoInitialize/RoUninitialize calls; simplified COM cleanup logic by removing redundant checks in CoUninitialize(), CleanupCOMState(), and SetApartment() |
| src/coreclr/nativeaot/System.Private.CoreLib/src/System/Threading/Thread.NativeAot.Windows.cs | Removed ENABLE_WINRT conditionals, now always using CoInitializeEx/CoUninitialize instead of RoInitialize/RoUninitialize |
| src/native/corehost/apphost/static/CMakeLists.txt | Removed RuntimeObject.lib linking dependency |
| src/coreclr/jit/CMakeLists.txt | Removed RuntimeObject.lib linking dependency |
| src/coreclr/ildasm/exe/CMakeLists.txt | Removed RuntimeObject.lib linking dependency |
| src/coreclr/ilasm/CMakeLists.txt | Removed RuntimeObject.lib linking dependency |
| src/coreclr/dlls/mscoree/coreclr/CMakeLists.txt | Removed RuntimeObject.lib linking dependency |
AaronRobinsonMSFT
approved these changes
Jan 7, 2026
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/ba-g DeadLetter |
This was referenced Jan 9, 2026
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Description
Removes redundant WinRT initialization code. Standard COM initialization via
CoInitializeEx/CoUninitializeis sufficient for COM/WinRT interop.Changes:
TSNC_WinRTInitializedthread state flag and associated methods (IsWinRTInitialized,ResetWinRTInitialized,BaseWinRTUninitialize)RoInitialize/RoUninitializecalls from CoreCLR thread apartment setupENABLE_WINRTconditional compilation from NativeAOT - now always usesCoInitializeExRuntimeObject.libdependency from build configurations (no longer needed)IsCoInitialized()checks in three locationsFiles modified:
src/coreclr/vm/threads.{h,cpp}- Thread state and COM initialization cleanupsrc/coreclr/nativeaot/.../Thread.NativeAot.Windows.cs- NativeAOT COM initializationCustomer Impact
None. This is internal runtime cleanup with no customer-facing behavior changes. COM/WinRT interop continues to work through standard COM infrastructure.
Regression
No. This removes code, does not change existing behavior.
Testing
Risk
Low. Changes are deletions of redundant initialization code and simplification of conditional logic. COM initialization remains intact via
CoInitializeEx, which already handles COM/WinRT threading requirements.Original prompt
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