.. _release-9-4-2:

Version 9.4.2
==============

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

The :ghc-flag:`LLVM backend <-fllvm>` of this release is to be used with LLVM
10, 11, 12, or 13.

Significant Changes
~~~~~~~~~~~~~~~~~~~~

This is primarily a bug-fix release addressing packaging issues found in 9.4.1.
These issues include:

 * Building with the ``make`` build system should now work reliably with
   GHC 9.0 (:ghc-ticket:`21897`, :ghc-ticket:`22047`)
 * Make-built binary distributions should no longer complain about incorrect
   GHC versions during installation (:ghc-ticket:)
 * Generated Haddock package index pages uploaded to Hackage lacked quick-jump
   support (:ghc-ticket:`21984`)
 * Cross-package identifier referenced are now linked correctly in Haddock
   documentation (:ghc-ticket:`20001`)
 * Hadrian-built binary distributions no longer attempt to install documentation
   if documentation was not built (:ghc-ticket:`21976`)
 * Package registration files installed by Hadrian-built binary distributions now
   have the correct permissions

In addition, a few non-packaging issues have been resolved:

 * the :ghc-flag:`-no-link` flag no longer attempts to link (:ghc-ticket:`21866`)
 * a soundness issue in GHCi has been resolved (:ghc-ticket:`22042`,
   :ghc-ticket:`21083`)
 * a subtle race condition in the IO manager triggered by changing the
   capability count was fixed (:ghc-ticket:`21651`)
 * GHC no longer attempts to use the platform-reserved `x18` register on
   AArch64/Darwin (:ghc-ticket:`21964`)
 * GHC's internal linker is now able to resolve symbols provided by FreeBSD's
   built-in ``iconv`` implementation (:ghc-ticket:`20354`)
 * GHC is now able to correctly locate ``libc++`` on FreeBSD systems

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.

.. ghc-package-list::

    libraries/array/array.cabal:             Dependency of ``ghc`` library
    libraries/base/base.cabal:               Core library
    libraries/binary/binary.cabal:           Dependency of ``ghc`` library
    libraries/bytestring/bytestring.cabal:   Dependency of ``ghc`` library
    libraries/Cabal/Cabal/Cabal.cabal:       Dependency of ``ghc-pkg`` utility
    libraries/Cabal/Cabal-syntax/Cabal-syntax.cabal:  Dependency of ``ghc-pkg`` utility
    libraries/containers/containers/containers.cabal: Dependency of ``ghc`` library
    libraries/deepseq/deepseq.cabal:         Dependency of ``ghc`` library
    libraries/directory/directory.cabal:     Dependency of ``ghc`` library
    libraries/exceptions/exceptions.cabal:   Dependency of ``ghc`` and ``haskeline`` library
    libraries/filepath/filepath.cabal:       Dependency of ``ghc`` library
    compiler/ghc.cabal:                      The compiler itself
    libraries/ghci/ghci.cabal:               The REPL interface
    libraries/ghc-boot/ghc-boot.cabal:       Internal compiler library
    libraries/ghc-boot-th/ghc-boot-th.cabal: Internal compiler library
    libraries/ghc-compact/ghc-compact.cabal: Core library
    libraries/ghc-heap/ghc-heap.cabal:       GHC heap-walking library
    libraries/ghc-prim/ghc-prim.cabal:       Core library
    libraries/haskeline/haskeline.cabal:     Dependency of ``ghci`` executable
    libraries/hpc/hpc.cabal:                 Dependency of ``hpc`` executable
    libraries/integer-gmp/integer-gmp.cabal: Core library
    libraries/libiserv/libiserv.cabal:       Internal compiler library
    libraries/mtl/mtl.cabal:                 Dependency of ``Cabal`` library
    libraries/parsec/parsec.cabal:           Dependency of ``Cabal`` library
    libraries/pretty/pretty.cabal:           Dependency of ``ghc`` library
    libraries/process/process.cabal:         Dependency of ``ghc`` library
    libraries/stm/stm.cabal:                 Dependency of ``haskeline`` library
    libraries/template-haskell/template-haskell.cabal: Core library
    libraries/terminfo/terminfo.cabal:       Dependency of ``haskeline`` library
    libraries/text/text.cabal:               Dependency of ``Cabal`` library
    libraries/time/time.cabal:               Dependency of ``ghc`` library
    libraries/transformers/transformers.cabal: Dependency of ``ghc`` library
    libraries/unix/unix.cabal:               Dependency of ``ghc`` library
    libraries/Win32/Win32.cabal:             Dependency of ``ghc`` library
    libraries/xhtml/xhtml.cabal:             Dependency of ``haddock`` executable