Go 1.5 Is Still Working Towards Being Written In Go

The plan for the upcoming release of Google's Go 1.5 language is to have its tool-chain be written in Go. In order to bootstrap the new Go compiler tool-chain, they'll depend on Go 1.4 to compile the new code.

Russ Cox has laid out the plans for the Go 1.5 bootstrap in order to eliminate all C programs/code from the Go source tree. The C code that remains in the Go source tree is being converted over to Go, so now in order to compile Go it needs to be boot-strapped using the Go 1.4 release.

When building Go 1.5 and higher, Go 1.4 will serve as the base compiler for the build process. After building the new compiler tool-chain, the new version of Go will then proceed to rebuild itself.

While this is reaching the point of Go being self-hosting, it will introduce complications when porting Go to new architectures/platforms. For those curious what the plans are for how these Go 1.5 issues will be addressed, see the Go 1.5 bootstrap plans on Google Docs.

Another prominent Go change recently was to move from Mercurial to Git and it's also planning to ship with numerous new features and improvements.