GHC 9.6.1-alpha2 is now available

bgamari - 2023-01-30

The GHC team is very pleased to announce the availability of GHC 9.6.1-alpha2. As usual, binaries and source distributions are available at downloads.haskell.org.

Beginning with GHC 9.6.1, GHC can be built as a cross-compiler to WebAssembly and JavaScript. This is an important step towards robust support for compiling Haskell to the Web, but there are a few caveats to be aware of in the 9.6 series:

Both the Javascript and WebAssembly backends are still at an early stage of development and are present in this release as a technology preview
Using GHC as a cross-compiler is not as easy as we would like it to be; in particular, there are challenges related to Template Haskell
GHC is not yet run-time retargetable; a given GHC binary targets exactly one platform, and both WebAssembly and JavaScript are considered platforms for this purpose. Cross-compilers must be built from source by their users

We hope to lift all of these limitations in future releases.

Additionally, 9.6.1 will include:

Significant latency improvements in the non-moving garbage collector
Efficient runtime support for delimited continuations
Improvements in compiler error messages
Numerous improvements in the compiler’s memory usage

See the release notes for a comprehensive accounting of changes in this release.

As always, one can find a migration guide to aid in transitioning from older releases on the GHC Wiki. We have also recently started extending our release process to cover a wider set of Linux distributions. In particular, we now offer Rocky 8 and Ubuntu 20.04 binary distributions which cover RedHat-derivative and distributions using older glibc releases (namely 2.27), respectively.

Please do give this release a try and open a ticket if you see anything amiss.

Cheers,