Managed array of integers and System::Void's

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Those 4 lines create a managed array of integers (System::Int32 value type). I prefer the syntax of the first version but I would understand people using the 4th:

Int32 mai[] = new Int32[2] ;

Int32 mai_1 __gc [] = new Int32[2] ;

Int32 mai_2[] = __gc new Int32[2] ;

int   mai_3 __gc [] = new int __gc [2] ;

 

The 4th does require the __gc on each side. They are compiled to the same IL:

IL_0043: ldc.i4.2

IL_0044: newarr [mscorlib]System.Int32

IL_0049: stloc.s V_5

IL_004b: ldloc.s V_5

IL_004d: call instance void [mscorlib]System.Array::Initialize()

IL_0052: ldloc.s V_5

IL_0054: stloc.s mai

The following line creates a native array of integers:

int * nativeArrayOfInt = new int[2] ;

delete nativeArrayOfInt ;

  

Of course, it produces quite different IL:

IL_0073: ldc.i4.8

IL_0074: call void * modopt ( [mscorlib] System.Runtime.CompilerServices.CallConvCdecl ) 'new[]' ( unsigned int32 )

IL_0079: stloc.s nativeArrayOfInt

You cannot create a managed array of System::Void structures even by inserting __gc all over the places ;-)

System::Void arrayOfVoidManagedPointer __gc [] = __gc new System::Void __gc [2] ; // Error

By the way, the Void Structure documentation says "This structure has no members, and you cannot create an instance of this structure.” .

Well, it does have a Void Members link. I reported the bug even if I might be missing the point.

 

For all practical purpose, "System::Object *" is the managed version of the native "void *"

 

À bientôt / Hasta el rato / 'til next time.