I still don't understand how these arguments make sense for new code. Naturally, sizes should be unsigned because they represent values which cannot be unsigned. If you do pointer/size arithmetic, the only solution to avoid overflows is to overflow-check and range-check before computation.

You cannot even check the signedness of a signed size to detect an overflow, because signed overflow is undefined!

The remaining argument from what I can tell is that comparisons between signed and unsigned sizes are bug-prone. There is however, a dedicated warning to resolve this instantly.

It makes sense that you should be able to assign a pointer to a size. If the size is signed, this cannot be done due to its smaller capacity.

Given this, I can't understand the justification. I'm currently using unsigned sizes. If you have anything contradicting, please comment :^)