Go 1.20.4 was released on May 2, 2023, and includes four changes to the language, as well as bug fixes to the compiler, the go command, the linker, the runtime, and the standard library.

Changes to the language

• The ability to convert a slice to an array.
• The addition of three new functions to the unsafe package: SliceData, String, and StringData.
• A new way of handling the compiler's internal data, which fixes several generic-types issues and enables type declarations within generic functions and methods.
• The compiler now rejects anonymous interface cycles with a compiler error by default.

Bug fixes

• Security fixes to the html/template package.
• Bug fixes to the compiler, the runtime, and the crypto/subtle, crypto/tls, net/http, and syscall packages.

The ability to convert a slice to an array

In Go 1.20.4, you can now convert a slice to an array. This is done using the new []T(x) syntax, where x is the slice to be converted. For example:

slice := []int{1, 2, 3}
array := []int(slice)

This will create a new array containing the same elements as the slice.

The addition of three new functions to the unsafe package

The unsafe package in Go provides access to low-level operations that are not safe to use in most cases. In Go 1.20.4, three new functions were added to the unsafe package:

• SliceData returns the underlying data for a slice.
• String returns the string representation of a slice.
• StringData returns the underlying data for a string.

These functions can be used to access the underlying data of a slice or string, which can be useful for low-level operations such as memory manipulation.

A new way of handling the compiler's internal data

The Go compiler uses a variety of internal data structures to represent the program being compiled. In Go 1.20.4, a new way of handling these data structures was introduced. This new way of handling the data structures fixes several generic-types issues and enables type declarations within generic functions and methods.

The compiler now rejects anonymous interface cycles with a compiler error by default

In Go, an anonymous interface is an interface that is declared without a name. Anonymous interfaces can be used to create closures, which are functions that can access variables from the surrounding scope.

In Go 1.20.4, the compiler now rejects anonymous interface cycles with a compiler error by default. An anonymous interface cycle is a situation where an anonymous interface contains a reference to itself. This can lead to errors, such as infinite recursion.

Bug fixes

In addition to the changes to the language, Go 1.20.4 also includes a number of bug fixes. These bug fixes address a variety of issues, including security vulnerabilities.

If you are using Go, I recommend that you upgrade to Go 1.20.4 as soon as possible. This will ensure that you are using the latest version of the language and that you are protected from security vulnerabilities.

I hope this blog post has been helpful. Please let me know if you have any other questions.