2.3. Version 9.2.3

The significant changes to the various parts of the compiler are listed in the following sections.

The LLVM backend of this release is to be used with LLVM 9, 10, 11, or 12.

2.3.1. Compiler

  • Fix a bug causing compiler panics on certain RULE declarations (#20820).

  • Fix a typechecker regression on certain programs involving type families and type equality constraints (#21473, #21515).

  • Fix a typechecker regression affecting programs involving quantified constraints and superclasses (#20582)

  • Fix a typechecker bug causing compiler panics on certain programs involing GADTs and Type Families (#20820).

  • Fix a typechecker panic on certain programs involving typed holes (#21130).

  • Fix a typechecker panic arising from uninferrable variables in a pattern synonym (#21479).

  • Various other typechecker bug fixes (#21531, #21516, #21519).

  • Ensure that XMM registers are preserved according to the calling convention on Win64 (#21465).

  • Fix a bug in the STG pipeline leading to segfaults in certain situations (#21396).

  • Fix a code generator bug causing CAFs to be incorrectly GC’d (#20959).

  • Improve error messages for OverloadedRecordFields in the case of ambiguous fields (#17420).

  • Improve warnings for redundant constraints (#20602).

2.3.2. Runtime system

  • Fix a bug with RTS accounting resulting in computing incorrect and negative productivity stats (#21082).

2.3.3. GHCi

  • Fix a bug causing certain type signatures to be pretty printed in a unpleasant way (#20974).

2.3.4. Core libraries

  • Bump bytestring to 0.11.3.1 fixing a critical linking bug causing GHC 9.2.2 to be unusable on Windows (#21196).

  • base: Export GHC.Event.Internal on Windows (#21245).

2.3.5. Build system and packaging

  • Use POSIX compatible shell syntax for redirecting output during configure (#20760).

  • Only copy and install libffi headers when using in-tree libffi (#21485, #21487).

  • Add support for bootstrapping hadrian without needing cabal-install.

  • Allow installing hadrian generated binary distributions to paths including the string “xxx” (#21402)

  • Allow bootstrapping from GHC 9.2.

  • Allow running the testsuite using Python 3.10.

2.3.6. Included libraries

The package database provided with this distribution also contains a number of packages other than GHC itself. See the changelogs provided with these packages for further change information.

Package Version Reason for inclusion

ghc

9.2.8

The compiler itself

Cabal

3.6.3.0

Dependency of ghc-pkg utility

Win32

2.12.0.1

Dependency of ghc library

array

0.5.4.0

Dependency of ghc library

base

4.16.4.0

Core library

binary

0.8.9.0

Dependency of ghc library

bytestring

0.11.4.0

Dependency of ghc library

containers

0.6.5.1

Dependency of ghc library

deepseq

1.4.6.1

Dependency of ghc library

directory

1.3.6.2

Dependency of ghc library

exceptions

0.10.4

Dependency of ghc and haskeline library

filepath

1.4.2.2

Dependency of ghc library

ghc-boot-th

9.2.8

Internal compiler library

ghc-boot

9.2.8

Internal compiler library

ghc-compact

0.1.0.0

Core library

ghc-heap

9.2.8

GHC heap-walking library

ghc-prim

0.8.0

Core library

ghci

9.2.8

The REPL interface

haskeline

0.8.2

Dependency of ghci executable

hpc

0.6.1.0

Dependency of hpc executable

integer-gmp

1.1

Core library

libiserv

9.2.8

Internal compiler library

mtl

2.2.2

Dependency of Cabal library

parsec

3.1.15.0

Dependency of Cabal library

pretty

1.1.3.6

Dependency of ghc library

process

1.6.16.0

Dependency of ghc library

stm

2.5.0.2

Dependency of haskeline library

template-haskell

2.18.0.0

Core library

terminfo

0.4.1.5

Dependency of haskeline library

text

1.2.5.0

Dependency of Cabal library

time

1.11.1.1

Dependency of ghc library

transformers

0.5.6.2

Dependency of ghc library

unix

2.7.2.2

Dependency of ghc library

xhtml

3000.2.2.1

Dependency of haddock executable