2.7. Version 9.2.7 — Glasgow Haskell Compiler 9.2.7 User's Guide

# 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