Hard time understanding the same line from 2 different .Net decompilers

Question

I have a hard time understanding what this code (c# .Net 4.5) i got from two different .Net decompilers does (ILSpy, dotPeek). ILSpy:

int num2;
int* arg_4C_0 = ref *(&num2);
*arg_4C_0 = 79;

dotPeek:

int num2;
IntPtr num3 = (IntPtr) &num2;
int num10 = 79;
*(int*) num3 = num10;

What exactly do they do? I can't follow them and none of those two implementations run on visual studio 2013(.Net framework 4.5.1 available).

Notice: the code is from winform application (PE 32-bit), directly imported in visual studio with dotPeek.