Blog / Go Language Spec

Pointer Arithmetic

January 21, 2025

I mentioned a few days ago that pointer arithmetic is possible through the unsafe package. Here’s how to do it.

Package unsafe

…

The function Add adds len to ptr and returns the updated pointer unsafe.Pointer(uintptr(ptr) + uintptr(len)) [Go 1.17]. The len argument must be of integer type or an untyped constant. A constant len argument must be representable by a value of type int; if it is an untyped constant it is given type int. The rules for valid uses of Pointer still apply.

I’m not going to go into when or why you would want to do pointer arithmetic. It’s something you should rarely ever do in Go, so counts as an advanced topic. And one I’m not especially versed in.

Quotes from The Go Programming Language Specification Language version go1.23 (June 13, 2024)

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