6. Release notes for version 8.4.4

6.1. Highlights

This is a bug-fix release resolving several regressions introduced in 8.4.1.

The highlights, since the 8.4.3 release, are:

• A bug which could result in memory unsafety with certain uses of touch# has been resolved. (Trac #14346)
• A compiler panic triggered by some GADT record updates has been fixed (Trac #15499)
• The text library has been updated, fixing several serious bugs in the version shipped with GHC 8.4.3 (see #227, #221, and #197.
• A serious code generation bug in the LLVM code generation, potentially resulting in incorrect evaluation of floating point expressions, has been fixed (Trac #14251)

6.2. Full details

In addition to the highlights listed above, this release resolves a number of other issues, described below.

6.2.1. Compiler

• A compiler panic triggered by case alternatives matching on invalid tags returned by dataToTag#, has been fixed (Trac #15436)
• Package environments can now be explicitly disabled using the new -package-env - flag. (Trac #13753)

6.2.2. Runtime system

No changes.

6.2.3. Template Haskell

No changes.

6.2.4. ghc library

No changes.

6.2.5. base library

• Version bumped to 4.11.1.0 to account for the addition of GHC.IO.FixIOException
• Add the readFieldHash function to GHC.Read which behaves like readField, but for a field that ends with a # symbol.

6.2.6. integer-gmp library

No changes.

6.2.7. Build system

No changes.

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	8.4.4	The compiler itself
Cabal	2.2.0.1	Dependency of ghc-pkg utility
Win32	2.6.1.0	Dependency of ghc library
array	0.5.2.0	Dependency of ghc library
base	4.11.1.0	Core library
binary	0.8.5.1	Dependency of ghc library
bytestring	0.10.8.2	Deppendency of ghc library
containers	0.5.11.0	Dependency of ghc library
deepseq	1.4.3.0	Dependency of ghc library
directory	1.3.1.5	Dependency of ghc library
filepath	1.4.2	Dependency of ghc library
ghc-boot	8.4.4	Internal compiler library
ghc-compact	0.1.0.0	Core library
ghc-prim	0.5.2.0	Core library
ghci	8.4.4	The REPL interface
haskeline	0.7.4.2	Dependency of ghci executable
hpc	0.6.0.3	Dependency of hpc executable
integer-gmp	1.0.2.0	Core library
mtl	2.2.2	Dependency of Cabal library
parsec	3.1.13.0	Dependency of Cabal library
process	1.6.3.0	Dependency of ghc library
template-haskell	2.13.0.0	Core library
text	1.2.3.1	Dependency of Cabal library
time	1.8.0.2	Dependency of ghc library
transformers	0.5.5.0	Dependency of ghc library
unix	2.7.2.2	Dependency of ghc library
xhtml	3000.2.2.1	Dependency of haddock executable