Thread by @mvdan_

Live tweeting from @GolangSheffield about what's coming to #golang 1.20, to be released at the end of January!

Follow along in the thread below 👇

@GolangSheffield We'll first look at upcoming toolchain changes.

A big new feature is profile-guided optimization:
go.dev/issue/55022

Distributed toolchain binaries work on glibc and musl:
go.dev/issue/54197

Binary distributions no longer include .a files:
go.dev/issue/47257

Extend coverage testing to include applications:
go.dev/issue/51430

go test gains a -skip flag:
go.dev/issue/41583

go test now prints running tests on timeout:
go.dev/issue/39038

bootstrapping 1.20 now requires Go 1.17 or later:
go.dev/issue/44505

New GO$GOARCH build tags:
go.dev/issue/45454

cmd/go removed the deprecated build -i flag:
go.dev/issue/41696

Onto API changes in the standard library!

Support wrapping multiple errors:
go.dev/issue/53435

Experimental arena support (!!!):
go.dev/issue/51317

crypto/ecdh, a better crypto/elliptic:
go.dev/issue/52221

time: add DateTime, DateOnly, TimeOnly:
go.dev/issue/52746

bytes,strings: add Clone:
go.dev/issue/45038

strings: add CutPrefix, CutSuffix:
go.dev/issue/42537

add testing.B.Elapsed:
go.dev/issue/43620

add io.OffsetWriter:
go.dev/issue/45899

reflect: add Comparable, Equal:
go.dev/issue/46746

add reflect.SetZero:
go.dev/issue/52376

add time.Time.Compare:
go.dev/issue/50770

Now onto performance improvements!

~0.3% smaller binaries via growslice:
go.dev/cl/418554

~1.1% smaller binaries via runtime.inlinedCall:
go.dev/issue/54849

~1% smaller ARM64 binaries:
go.dev/cl/444715

the compiler got ~3% faster:
go.dev/cl/432897

new inline heuristic for struct compares:
go.dev/issue/38494

time: ~70% faster at parsing and ~30% at formatting RFC3339:
go.dev/issue/54093

go/printer is now ~13% faster:
go.dev/cl/424924
go.dev/cl/412555

text/template parsing is now ~40% faster:
go.dev/issue/53261

large io.Copy calls via splice on Linux are now ~20% faster:
go.dev/cl/425051

-race is now 15% faster on GOAMD64=v3:
go.dev/cl/444396

That's it for today! Look forward to the first beta being released in a few weeks' time, and please test it :)