GHC 8.10.1-rc1 now available

bgamari - 2020-01-24

The GHC team is happy to announce the availability of the first release candidate of GHC 8.10.1. Source and binary distributions are available at the usual place.

GHC 8.10.1 will bring a number of new features including:

The new UnliftedNewtypes extension allowing newtypes around unlifted types.

The new StandaloneKindSignatures extension allows users to give top-level kind signatures to type, type family, and class declarations.

A new warning, -Wderiving-defaults , to draw attention to ambiguous deriving clauses

A number of improvements in code generation, including changes

A new GHCi command, :instances , for listing the class instances available for a type.

An upgraded Windows toolchain lifting the MAX_PATH limitation

A new, low-latency garbage collector.

Improved support profiling, including support for sending profiler samples to the eventlog, allowing correlation between the profile and other program events

This is the first and likely final release candidate. For a variety of reasons, it comes a few weeks later than the original schedule of release late December. However, besides a few core libraries book-keeping issues this candidate is believed to be in good condition for the final release. As such, the final 8.10.1 release will likely come in two weeks.

Note that at the moment we still require that macOS Catalina users exempt the binary distribution from the notarization requirement by running xattr -cr . on the unpacked tree before running make install .

In addition, we are still looking for any Alpine Linux to help diagnose the correctness issues in the Alpine binary distribution. If you use Alpine any you can offer here would be greatly appreciated.

Please do test this release and let us know if you encounter any other issues.