6. Release notes for version 8.8.4

GHC 8.8.4 is a minor release intended to fix regressions and minor bugs in the 8.8.1, 8.8.2 and 8.8.3 releases.

Like previous releases in the 8.8 series, the LLVM backend of this release is to be used with LLVM 7.

6.1. Highlights

  • Fixes a bug in process creation on Windows (Issue #17926).

  • Works around a Linux kernel bug in the implementation of timerfds (Issue #18033).

  • Fixes a few linking issues affecting ARM

  • Fixes “missing interface file” error triggered by some uses of Ordering (Issue #18185)

  • Fixes an integer overflow in the compact-normal-form import implementation (Issue #16992)

  • configure now accepts --enable-numa flag to enable/disable numactl support on Linux.

  • Fixes potentially lost sharing due to the desugaring of left operator sections (Issue #18151).

  • Fixes a build-system bug resulting in potential miscompilation by unregisteised compilers (Issue #18024)

6.2. Known issues

  • A long-standing bug (Issue #16893) which can cause some applications of unsafeCoerce to segmentation fault is only partially fixed in this release. This release only avoids this issue in the uses of unsafeCoerce in Data.Typeable.Internal, which was the proximate cause of Issue #16893.

    However, it is possible that this bug could manifest in user-code using unsafeCoerce to perform dynamic type checks. See the ticket for details.

  • The simplifier can optimise away some applications of the touch# primop when it can prove that the touch# is unreachable due to divergence or synchronous exception, resulting in memory unsoundness. Users requiring touch# behavior are advised to only use touch# to implement continuation-passing-style primitives (e.g. in the style of withForeignPtr) bearing NOINLINE pragmas (to avoid inappropriate simplification). See Issue #17760 for details.

6.3. 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

 8.8.4

The compiler itself

Cabal

 3.0.1.0

Dependency of ghc-pkg utility

Win32

 2.6.1.0

Dependency of ghc library

array

 0.5.4.0

Dependency of ghc library

base

 4.13.0.0

Core library

binary

 0.8.7.0

Dependency of ghc library

bytestring

 0.10.10.1

Dependency of ghc library

containers

 0.6.2.1

Dependency of ghc library

deepseq

 1.4.4.0

Dependency of ghc library

directory

 1.3.6.0

Dependency of ghc library

filepath

 1.4.2.1

Dependency of ghc library

ghc-boot-th

 8.8.4

Internal compiler library

ghc-boot

 8.8.4

Internal compiler library

ghc-compact

 0.1.0.0

Core library

ghc-heap

 8.8.4

GHC heap-walking library

ghc-prim

 0.5.3

Core library

ghci

 8.8.4

The REPL interface

haskeline

 0.7.5.0

Dependency of ghci executable

hpc

 0.6.0.3

Dependency of hpc executable

integer-gmp

 1.0.2.0

Core library

libiserv

 8.8.4

Internal compiler library

mtl

 2.2.2

Dependency of Cabal library

parsec

 3.1.14.0

Dependency of Cabal library

pretty

 1.1.3.6

Dependency of ghc library

process

 1.6.9.0

Dependency of ghc library

stm

 2.5.0.0

Dependency of haskeline library

template-haskell

 2.15.0.0

Core library

terminfo

 0.4.1.4

Dependency of haskeline library

text

 1.2.4.0

Dependency of Cabal library

time

 1.9.3

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