Updatify / Go lang | Release notes

go1.7.4 (released 2016-12-01) includes two security fixes. See the Go 1.7.4 milestone on our issue tracker for details.

go1.6.4 (released 2016-12-01) includes two security fixes. It contains the same fixes as Go 1.7.4 and was released at the same time. See the Go 1.7.4 milestone on our issue tracker for details.

go1.7.3 (released 2016-10-19) includes fixes to the compiler, runtime, and the crypto/cipher, crypto/tls, net/http, and strings packages. See the Go 1.7.3 milestone on our issue tracker for details.

go1.7.1 (released 2016-09-07) includes fixes to the compiler, runtime, documentation, and the compress/flate, hash/crc32, io, net, net/http, path/filepath, reflect, and syscall packages. See the Go 1.7.1 milestone on our issue tracker for details.

Introduction to Go 1.7

The latest Go release, version 1.7, arrives six months after 1.6. Most of its changes are in the implementation of the toolchain, runtime, and libraries. There is one minor change to the language specification. As always, the release maintains the Go 1 promise of compatibility. We expect almost all Go programs to continue to compile and run as before.

The release adds a port to IBM LinuxOne; updates the x86-64 compiler back end to generate more efficient code; includes the context package, promoted from the x/net subrepository and now used in the standard library; and adds support in the testing package for creating hierarchies of tests and benchmarks. The release also finalizes the vendoring support started in Go 1.5, making it a standard feature.

Changes to the language

There is one tiny language change in this release. The section on terminating statements clarifies that to determine whether a statement list ends in a terminating statement, the “final non-empty statement” is considered the end, matching the existing behavior of the gc and gccgo compiler toolchains. In earlier releases the definition referred only to the “final statement,” leaving the effect of trailing empty statements at the least unclear.

go1.6.3 (released 2016-07-17) includes security fixes to the net/http/cgi package and net/http package when used in a CGI environment. See the Go 1.6.3 milestone on our issue tracker for details.

go1.6.2 (released 2016-04-20) includes fixes to the compiler, runtime, tools, documentation, and the mime/multipart, net/http, and sort packages. See the Go 1.6.2 milestone on our issue tracker for details.

go1.6.1 (released 2016-04-12) includes two security fixes. See the Go 1.6.1 milestone on our issue tracker for details.

go1.5.4 (released 2016-04-12) includes two security fixes. It contains the same fixes as Go 1.6.1 and was released at the same time. See the Go 1.6.1 milestone on our issue tracker for details.

Introduction to Go 1.6

The latest Go release, version 1.6, arrives six months after 1.5. Most of its changes are in the implementation of the language, runtime, and libraries. There are no changes to the language specification. As always, the release maintains the Go 1 promise of compatibility. We expect almost all Go programs to continue to compile and run as before.

The release adds new ports to Linux on 64-bit MIPS and Android on 32-bit x86; defined and enforced rules for sharing Go pointers with C; transparent, automatic support for HTTP/2; and a new mechanism for template reuse.

Changes to the language

There are no language changes in this release.

Ports

Go 1.6 adds experimental ports to Linux on 64-bit MIPS ( linux/mips64 and linux/mips64le). These ports support cgo but only with internal linking.

Go 1.6 also adds an experimental port to Android on 32-bit x86 ( android/386).

On FreeBSD, Go 1.6 defaults to using clang, not gcc, as the external C compiler.

On Linux on little-endian 64-bit PowerPC ( linux/ppc64le), Go 1.6 now supports cgo with external linking and is roughly feature complete.

On NaCl, Go 1.5 required SDK version pepper-41. Go 1.6 adds support for later SDK versions.

On 32-bit x86 systems using the -dynlink or -shared compilation modes, the register CX is now overwritten by certain memory references and should

go1.5.3 (released 2016-01-13) includes a security fix to the math/big package affecting the crypto/tls package. See the release announcement for details.

go1.5.2 (released 2015-12-02) includes bug fixes to the compiler, linker, and the mime/multipart, net, and runtime packages. See the Go 1.5.2 milestone on our issue tracker for details.

go1.4.3 (released 2015-09-22) includes security fixes to the net/http package and bug fixes to the runtime package. See the Go 1.4.3 milestone on our issue tracker for details.

go1.5.1 (released 2015-09-08) includes bug fixes to the compiler, assembler, and the fmt, net/textproto, net/http, and runtime packages. See the Go 1.5.1 milestone on our issue tracker for details.

Introduction to Go 1.5

The latest Go release, version 1.5, is a significant release, including major architectural changes to the implementation. Despite that, we expect almost all Go programs to continue to compile and run as before, because the release still maintains the Go 1 promise of compatibility.

The biggest developments in the implementation are:

• The compiler and runtime are now written entirely in Go (with a little assembler). C is no longer involved in the implementation, and so the C compiler that was once necessary for building the distribution is gone.
• The garbage collector is now concurrent and provides dramatically lower pause times by running, when possible, in parallel with other goroutines.
• By default, Go programs run with GOMAXPROCS set to the number of cores available; in prior releases it defaulted to 1.
• Support for internal packages is now provided for all repositories, not just the Go core.
• The go command now provides experimental support for “vendoring” external dependencies.
• A new go tool trace command supports fine-grained tracing of program execution.
• A new go doc command (distinct from godoc) is customized for command-line use.

These and a number of other changes to the implementation and tools are discussed below.

The release also contains one small language change involving map literals.

go1.4.2 (released 2015-02-17) includes security fixes to the compiler, and bug fixes to the go command, the compiler and linker, and the runtime, syscall, reflect, and math/big packages. See the Go 1.4.2 milestone on our issue tracker for details.

go1.4.1 (released 2015-01-15) includes bug fixes to the linker and the log, syscall, and runtime packages. See the Go 1.4.1 milestone on our issue tracker for details.

Introduction to Go 1.4

The latest Go release, version 1.4, arrives as scheduled six months after 1.3.

It contains only one tiny language change, in the form of a backwards-compatible simple variant of for - range loop, and a possibly breaking change to the compiler involving methods on pointers-to-pointers.

The release focuses primarily on implementation work, improving the garbage collector and preparing the ground for a fully concurrent collector to be rolled out in the next few releases. Stacks are now contiguous, reallocated when necessary rather than linking on new “segments”; this release therefore eliminates the notorious “hot stack split” problem. There are some new tools available including support in the go command for build-time source code generation. The release also adds support for ARM processors on Android and Native Client (NaCl) and for AMD64 on Plan 9.

As always, Go 1.4 keeps the promise of compatibility, and almost everything will continue to compile and run without change when moved to 1.4.

Changes to the language

For-range loops

Up until Go 1.3, for - range loop had two forms

for i, v := range x {
    ...
}

and

for i := range x {
    ...
}

If one was not interested in the loop values, only the iteration itself, it was still

go1.3.3 (released 2014-09-30) includes further bug fixes to cgo, the runtime package, and the nacl port. See the change history for details.

go1.3.2 (released 2014-09-25) includes security fixes to the crypto/tls package and bug fixes to cgo. See the change history for details.

go1.3.1 (released 2014-08-13) includes bug fixes to the compiler and the runtime, net, and crypto/rsa packages. See the change history for details.

Introduction to Go 1.3

The latest Go release, version 1.3, arrives six months after 1.2, and contains no language changes. It focuses primarily on implementation work, providing precise garbage collection, a major refactoring of the compiler toolchain that results in faster builds, especially for large projects, significant performance improvements across the board, and support for DragonFly BSD, Solaris, Plan 9 and Google’s Native Client architecture (NaCl). It also has an important refinement to the memory model regarding synchronization. As always, Go 1.3 keeps the promise of compatibility, and almost everything will continue to compile and run without change when moved to 1.3.

Changes to the supported operating systems and architectures

Removal of support for Windows 2000

Microsoft stopped supporting Windows 2000 in 2010. Since it has implementation difficulties regarding exception handling (signals in Unix terminology), as of Go 1.3 it is not supported by Go either.

Support for DragonFly BSD

Go 1.3 now includes experimental support for DragonFly BSD on the amd64 (64-bit x86) and 386 (32-bit x86) architectures. It uses DragonFly BSD 3.6 or above.

Support for FreeBSD

It was not announced at the time, but since the release of Go 1.2, support for Go on FreeBSD requires FreeBSD 8 or above.

go1.2.2 (released 2014-05-05) includes a security fix that affects the tour binary included in the binary distributions (thanks to Guillaume T).

go1.2.1 (released 2014-03-02) includes bug fixes to the runtime, net, and database/sql packages. See the change history for details.

Introduction to Go 1.2

Since the release of Go version 1.1 in April, 2013, the release schedule has been shortened to make the release process more efficient. This release, Go version 1.2 or Go 1.2 for short, arrives roughly six months after 1.1, while 1.1 took over a year to appear after 1.0. Because of the shorter time scale, 1.2 is a smaller delta than the step from 1.0 to 1.1, but it still has some significant developments, including a better scheduler and one new language feature. Of course, Go 1.2 keeps the promise of compatibility. The overwhelming majority of programs built with Go 1.1 (or 1.0 for that matter) will run without any changes whatsoever when moved to 1.2, although the introduction of one restriction to a corner of the language may expose already-incorrect code (see the discussion of the use of nil).

Changes to the language

In the interest of firming up the specification, one corner case has been clarified, with consequences for programs. There is also one new language feature.

Use of nil

The language now specifies that, for safety reasons, certain uses of nil pointers are guaranteed to trigger a run-time panic. For instance, in Go 1.0, given code like

type T struct {
    X [1<<24]byte
    Field int32
}

func main() {
    var x *T
    ...
}

the nil pointer x could be used to access memory incorrectly:

go1.1.2 (released 2013-08-13) includes fixes to the gc compiler and cgo, and the bufio, runtime, syscall, and time packages. See the change history for details. If you use package syscall’s Getrlimit and Setrlimit functions under Linux on the ARM or 386 architectures, please note change 11803043 that fixes issue 5949.

go1.1.1 (released 2013-06-13) includes a security fix to the compiler and several bug fixes to the compiler and runtime. See the change history for details.

Introduction to Go 1.1

THE RELEASE of Go version 1 (Go 1 or Go 1.0 for short) in March of 2012 introduced a new period of stability in the Go language and libraries. That stability has helped nourish a growing community of Go users and systems around the world. Several “point” releases since then—1.0.1, 1.0.2, and 1.0.3—have been issued. These point releases fixed known bugs but made no non-critical changes to the implementation.

This new release, Go 1.1, keeps the promise of compatibility but adds a couple of significant (backwards-compatible, of course) language changes, has a long list of (again, compatible) library changes, and includes major work on the implementation of the compilers, libraries, and run-time. The focus is on performance. Benchmarking is an inexact science at best, but we see significant, sometimes dramatic speedups for many of our test programs. We trust that many of our users’ programs will also see improvements just by updating their Go installation and recompiling.

This document summarizes the changes between Go 1 and Go 1.1. Very little if any code will need modification to run with Go 1.1, although a couple of rare error cases surface with this release and need to be addressed if they arise. Details appear below; see the discussion of 64-bit ints and Unicode literals in particular.

Changes to the language

go1.0.3 (released 2012-09-21) includes minor code and documentation fixes.

go1.0.2 (released 2012-06-13) was issued to fix two bugs in the implementation of maps using struct or array keys: issue 3695 and issue 3573. It also includes many minor code and documentation fixes.

go1.0.1 (released 2012-04-25) was issued to fix an escape analysis bug that can lead to memory corruption. It also includes several minor code and documentation fixes.

Introduction to Go 1

Go version 1, Go 1 for short, defines a language and a set of core libraries that provide a stable foundation for creating reliable products, projects, and publications.

The driving motivation for Go 1 is stability for its users. People should be able to write Go programs and expect that they will continue to compile and run without change, on a time scale of years, including in production environments such as Google App Engine. Similarly, people should be able to write books about Go, be able to say which version of Go the book is describing, and have that version number still be meaningful much later.

Code that compiles in Go 1 should, with few exceptions, continue to compile and run throughout the lifetime of that version, even as we issue updates and bug fixes such as Go version 1.1, 1.2, and so on. Other than critical fixes, changes made to the language and library for subsequent releases of Go 1 may add functionality but will not break existing Go 1 programs. The Go 1 compatibility document explains the compatibility guidelines in more detail.

Go 1 is a representation of Go as it used today, not a wholesale rethinking of the language. We avoided designing new features and instead focused on cleaning up problems and inconsistencies and improving portability. There are a number changes to the Go language and packages that we had considered for some time and

go1.7.2 should not be used. It was tagged but not fully released. The release was deferred due to a last minute bug report. Use go1.7.3 instead, and refer to the summary of changes below.