Yes, you can do this in C++, but keep in mind that implicitly generated copy/move constructors don't understand this and will not copy the full object. This can produce surprising memory corruption that can be difficult to debug. So you should be sure to either explicitly mark the struct not copy/movable, or implement smarter copy/move operators.
Tbf I don't think C copies the whole flexible array member either[0]. So the care you would normally take while using a flexible array member in C should also be taken in C++ :)
