GHC 9.0.2 is now available

Zubin Duggal - 2021-12-25

The GHC developers are very happy to at long last announce the availability of GHC 9.0.2. Binary distributions, source distributions, and documentation are available at downloads.haskell.org.

GHC 9.0.2 adds first class AArch64/Darwin support using the LLVM backend, as well as fixing a number of critical correctness bugs with the 9.0.1 release, along with numerous improvements to compiler performance and memory usage:

• First-class support for Apple M1 hardware using GHC’s LLVM ARM backend.

• Fix a number of incorrect rewrite rules for fromInteger (#19345, #20066).

• Fix a number of runtime system and GC bugs which typically manifested in crashes (#19417, #19297, #19645, #19667, #18033, #20132, #19715, #20399, #20414, #20649, #19147, #20051, #20093)

• Fixes for various compiler performance and memory usage issues (#20134, #13586, #20509, #19668, #19996, #19471)

• Improvements and bug fixes for the code generator and optimiser (#18638, #19581, #19700, #19996, #19181, #19822)

• Fixes for typechecker bugs (#19410 , #19191, #19522, #19400, #19849)

• Bug fixes for the frontend and parser (#19397, #19838, #19518, #19777, #20242, #19786)

• Emit warnings if Unicode Bidirectional Formatting characters are found in the source, possibly misleading code reviewers (#20263, vulnerability website).

• Many packaging related fixes, including versioned ghc-pkg executables (#20087), and actually distributing GHC versions linked against the native big integer backend (#18967, #19953) on both Windows and Alpine Linux. Some previous releases were still linked against the GMP library due to a misconfiguration of the builders.

• A significant refactoring of process fixing numerous bugs mostly on Apple platforms (#19994, process refactoring).

• Bug fixes for the linker on Darwin platforms (#20004, #19968, #19950).

A complete list of bug fixes and improvements can be found in the release notes.

Finally, thank you to Microsoft Research, GitHub, IOHK, the Zw3rk stake pool, Tweag I/O, Serokell, Equinix, SimSpace, and other anonymous contributors whose on-going financial and in-kind support has facilitated GHC maintenance and release management over the years. Moreover, this release would not have been possible without the hundreds of open-source contributors whose work comprise this release.

As always, do open a ticket if you see anything amiss.