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 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 Dependency of ghc-pkg utility
Win32 Dependency of ghc library
array Dependency of ghc library
base Core library
binary Dependency of ghc library
bytestring Dependency of ghc library
containers Dependency of ghc library
deepseq Dependency of ghc library
directory Dependency of ghc library
exceptions 0.10.4 Dependency of ghc and haskeline library
filepath Dependency of ghc library
ghc-boot-th 9.2.8 Internal compiler library
ghc-boot 9.2.8 Internal compiler library
ghc-compact 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 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 Dependency of Cabal library
pretty Dependency of ghc library
process Dependency of ghc library
stm Dependency of haskeline library
template-haskell Core library
terminfo Dependency of haskeline library
text Dependency of Cabal library
time Dependency of ghc library
transformers Dependency of ghc library
unix Dependency of ghc library
xhtml 3000.2.2.1 Dependency of haddock executable