Log Message:
Update Go to 1.9.

The latest Go release, version 1.9, arrives six months after Go 1.8 and
is the tenth release in the Go 1.x series. There are two changes to the
language: adding support for type aliases and defining when
implementations may fuse floating point operations. Most of the changes
are in the implementation of the toolchain, runtime, and libraries. 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 transparent monotonic time support, parallelizes
compilation of functions within a package, better supports test helper
functions, includes a new bit manipulation package, and has a new
concurrent map type.

There are some instabilities on FreeBSD that are known but not
understood. These can lead to program crashes in rare cases. See issue
15658. Any help in solving this FreeBSD-specific issue would be
appreciated.

Go stopped running NetBSD builders during the Go 1.9 development cycle
due to NetBSD kernel crashes, up to and including NetBSD 7.1. As Go 1.9
is being released, NetBSD 7.1.1 is being released with a fix. However,
at this time we have no NetBSD builders passing our test suite. Any help
investigating the various NetBSD issues would be appreciated.