Today’s article looks at the IL2CPP and C++ compiler output for a variety of C# language features. Do you want to know what happens when you use them? Read on to find out!
Posts Tagged sizeof
I continue to learn a lot by reading the C++ code that IL2CPP outputs. Like reading decompiled code, it gives some insight into what what Unity’s build process is doing with the C# we give it. This week I learned that sizeof(MyStruct) isn’t a compile-time constant like it is in C++. Because of that, IL2CPP generates some less-than-ideal C++ code every time you use it. Today’s article shows the process I went through to work around that issue and ends up with some code you can drop into your project to avoid the problem.
Structs can be a great way to keep the garbage collector off your back and to use the CPU’s data cache more effectively. Not everything can be a struct though. At a minimum, you’ll need to use some Unity and .NET classes like MonoBehaviour and string. If your struct has any of these as fields, you can no longer use sizeof(MyStruct). That really limits its usefulness, so a workaround is needed. Enter object handles: a simple way to represent any object as a plain old int which won’t break sizeof. Read on to see how these work and some code you can easily drop into your project to start using them right away!