2.7. Version 9.2.7

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.

2.7.1. Compiler

  • Fix a bug related to placeholder values (rubbish literals) emitted by the worker/wrapper optimisation leading to -dcore-lint errors and compiler panics in certain cases (#19882, #22914, #23000).
  • Fix a bug with the graph-colouring register allocater leading to compiler panics when compiling with -fregs-graph on AArch64 platforms with the native code generator. A fix was also attempted in GHC 9.2.6 but was incomplete (#22798, #23002).

2.7.2. Runtime system

  • Fix a bug with the RTS linker being unable to resolve the setKeepCAFs symbol which started being used by the GHC library in 9.2.6, resulting in code depending on this symbol failing to load in GHCi or via a compile time splice when using a statically linked GHC, such as on Windows (#22961).
  • Fix a bug with the alignment of RTS data structures that could result in segfaults when compiled with high optimisation settings on certain platforms (#22975 , #22965).
  • Fix a RTS bug resulting in segfaults while using cost center profiling on code that uses the newArrayArray# primop (#22129).
  • Use C11 compatible static assertion syntax (#22777).

2.7.3. Build system and packaging

  • Remove quarantine attribute when installing binary distribution on MacOS (#21506, #23009).
  • Enable SMP on powerp64{le} (#19825).

2.7.4. 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 9.2.7 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 9.2.7 Internal compiler library
ghc-boot 9.2.7 Internal compiler library
ghc-compact 0.1.0.0 Core library
ghc-heap 9.2.7 GHC heap-walking library
ghc-prim 0.8.0 Core library
ghci 9.2.7 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 9.2.7 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