"GetFuncPtr() with SuppressGCTransition Applied"

[DllImport("NativeLib.dll", CallingConvention = CallingConvention.Cdecl), SuppressGCTransition]
public static unsafe extern void GetFuncPtr(delegate* unmanaged<char*>* outFuncPtr);


Code snippet taken from "Two Decades of C#: A Reference - C# 9".