gcUnmanagedToManaged MDA
Note
This article is specific to .NET Framework. It doesn't apply to newer implementations of .NET, including .NET 6 and later versions.
The gcUnmanagedToManaged managed debugging assistant (MDA) causes a garbage collection whenever a thread transitions from unmanaged to managed code.
Symptoms
An application running unmanaged user components using COM and platform invoke is causing a nondeterministic access violation in the CLR.
Cause
If an application is running unmanaged user components, then those components might have corrupted the garbage-collected heap. This causes an access violation in the CLR when the garbage collector tries to walk the object graph.
Resolution
Enabling this assistant reduces the time between when the unmanaged component corrupts the garbage-collected heap and when the access violation happens by forcing a garbage collection to occur before every managed transition.
Effect on the Runtime
Causes a garbage collection whenever a thread transitions from unmanaged to managed code.
Output
This MDA produces no output.
Configuration
<mdaConfig>
<assistants>
<gcUnmanagedToManaged/>
</assistants>
</mdaConfig>
