Debugging C compilers have been using "fat pointer" implementations for decades, to do bounds checking, but of course it's dangerous to use that into C code tha

Debugging C compilers have been using "fat pointer" implementations for decades, to do bounds checking, but of course it's dangerous to use that into C code that assumes things about the sizes of pointers. Fortran added array descriptors in 1990, when it made arrays first class objects. That was a quite visible language change. So this is a well-studied area with lots of implementations you can look at.