Fix marshalling generators using 0 as cleanup length for ManagedToUnmanaged collections with NoCountInfo#126853
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Fix marshalling generators using 0 as cleanup length for ManagedToUnmanaged collections with NoCountInfo#126853
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… arrays of jagged 2D arrays When the marshalling direction is ManagedToUnmanaged and there is no explicit count info (NoCountInfo), the cleanup code was setting numElements = 0, causing Free to never be called on inner array elements. This fix uses GetManagedValuesSource().Length instead to get the actual element count from the managed collection. Fixes #93423 Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/3665c6a3-655d-4215-a791-d3a838f80bd4 Co-authored-by: jtschuster <36744439+jtschuster@users.noreply.github.com>
…esSource Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/3665c6a3-655d-4215-a791-d3a838f80bd4 Co-authored-by: jtschuster <36744439+jtschuster@users.noreply.github.com>
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[WIP] Fix marshalling cleanup for inner arrays of jagged 2D arrays
Fix marshalling generators using 0 as cleanup length for ManagedToUnmanaged collections with NoCountInfo
Apr 13, 2026
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Description
When marshalling collections ManagedToUnmanaged with no explicit count info (e.g., inner arrays of jagged 2D arrays with element marshallers that have
Free), the source generator emittednumElements = 0during cleanup. This caused the cleanup loop to never execute, leaking unmanaged memory on every successful call.The fix replaces the hardcoded
0withGetManagedValuesSource().Length, which is the correct element count for ManagedToUnmanaged cleanup — the managed collection is the source of truth.Before (generated cleanup code):
After:
Changes
ElementsMarshalling.cs— ExposeGenerateNumElementsAssignmentFromManagedValuesSource()on the base class, wrapping the existingfile staticextension method so it's callable fromStatelessMarshallingStrategy.csStatelessMarshallingStrategy.cs— ReplacenumElements = 0with the managed values source length inGenerateCleanupCallerAllocatedResourcesStatementsElementInWithFreemarshaller andNonBlittableElementWithFreeByValuetest cases for both stateless/stateful paths in LibraryImportGenerator and ComInterfaceGenerator unit tests