VariableLengthInlineArray and method return

[Ephron-WL]

Actual behavior

SP_DEVICE_INTERFACE_DETAIL_DATA_W is generated with a property DevicePath of type VariableLengthInlineArray<char>

An instance of SP_DEVICE_INTERFACE_DETAIL_DATA_W is used as an argument to SetupDiGetDeviceInterfaceDetail.

To obtain the DevicePath value I use new string(&detail.DeviocePath.eb0). This works great. If I execute this code within any method other than the Main method, I get an access violation at the point in which the method returns. If I create the SP_DEVICE_INTERFACE_DETAIL_DATA_W inside of the Main method and pass a pointer into the method and instantiate the string in the Main method, it works.

Great library, otherwise.

Expected behavior

I would expect to be able to execute my code within a method other than Main and return the results in the form of a string from a method other than Main.

Repro steps

1. NativeMethods.txt content:

   
   SetupDiGetClassDevs
   CreateFile
   DeviceIoControl
   SetupDiGetDeviceInterfaceDetail
   SetupDiEnumDeviceInterfaces
   DISK_GEOMETRY_EX
   ReadFile
   SetFilePointer
   FSCTL_ALLOW_EXTENDED_DASD_IO
   STORAGE_PROPERTY_QUERY
   STORAGE_DEVICE_DESCRIPTOR
   IOCTL_STORAGE_GET_DEVICE_NUMBER
   IOCTL_STORAGE_QUERY_PROPERTY
   STORAGE_DEVICE_NUMBER
   DRIVE_LAYOUT_INFORMATION_EX
   IOCTL_DISK_GET_PARTITION_INFO_EX
   DRIVE_LAYOUT_INFORMATION
   IOCTL_DISK_GET_PARTITION_INFO
   PARTITION_INFORMATION_EX
   IOCTL_DISK_GET_DRIVE_LAYOUT_EX 
   IOCTL_DISK_GET_DRIVE_GEOMETRY_EX
   GENERIC_ACCESS_RIGHTS

2. `NativeMethods.json` content (if present):
```json
{
  "$schema": "https://aka.ms/CsWin32.schema.json",
  "emitSingleFile": true,
  "public": true
}

3. Any of your own code that should be shared?

   Context

• CsWin32 version: [e.g. 0.4.422-beta] 0.3.106
• Win32Metadata version (if explicitly set by project): 60.0.34-preview
• Target Framework: [e.g. netstandard2.0] core 8
• LangVersion (if explicitly set by project): [e.g. 9]

[Ephron-WL]

Rookie mistake. When the method returns references to unmanaged memory are lost. To return a string, even if the string is copied, requires that the unmanaged memory remain, I presume due to compilation optimizations leading to memory assignments that avoid allocating to the heap. By assigning variables that hold unmanaged memroy to a context that survives method calls I can ensure the memory remains accessible.