Skip to main content
Version: 2.9.x(Latest)

Go 1.23 (2024-08-13)

Go 1.23 was released in August 2024, introducing iterator support, telemetry, and toolchain improvements.

Major Changes​

Language​

  • Range-over-func (Iterators): for-range loops now support user-defined iterator functions. This allows developers to create standard iteration interfaces for custom containers.
  • Generic Type Aliases: Introduced preview support for generic type aliases (enabled via GOEXPERIMENT=aliastypeparams).

Toolchain​

  • Go Telemetry: Introduced an optional telemetry system to help the Go team understand toolchain usage and performance issues. Users can opt-in or opt-out at any time (go telemetry on).
  • Go Command:
    • go env -changed: Lists only environment variables that differ from their default values.
    • go mod tidy -diff: Prints the necessary changes as a diff instead of modifying files.
    • godebug directive: Declare GODEBUG settings in go.mod and go.work.
  • Vet: Added stdversion analyzer, which flags references to symbols that are too new for the current Go version.
  • Trace: The trace tool is now more tolerant of partially corrupted trace data, especially when the program crashes.

Runtime​

  • PGO Improvements: Significantly reduced build time overhead when PGO is enabled.
  • Stack Usage Optimization: The compiler can now overlap stack frame slots for local variables in disjoint regions of a function, reducing stack usage.
  • Linker: The linker now prohibits the use of //go:linkname to reference internal symbols in the standard library that are not marked for export.

Standard Library​

  • iter: Added iter package, defining basic types and functions for iterators.
  • slices and maps: Added support for iterators, such as slices.All, slices.Collect, maps.Keys, maps.Values, etc.
  • unique: Added unique package for deduplicating immutable values via interning.
  • structs: Added structs package, providing HostLayout type to control struct memory layout.
  • time: Garbage collection for Timer and Ticker has been improved, no longer requiring explicit Stop calls to prevent memory leaks. Associated channels are now unbuffered.
  • net/http: Cookie handling improvements (preserving quotes, supporting Partitioned attribute), ServeMux patterns support spaces.
  • reflect: Added Value.Seq and Value.Seq2 methods to support iteration over reflected values.

References​

For more details, please refer to the official release notes: Go 1.23 Release Notes