4. Release notes for version 8.4.2¶
4.1. Highlights¶
This is a bug-fix release resolving several regressions introduced in 8.4.1.
The highlights, since the 8.4.1 release, are:
- Fixed a regression causing uses of
Control.Exception.evaluateto be incorrectly optimised, resulting in incorrect evaluation behavior (Trac #13930) - Fix a regression causing the interpreter to segmentation fault when built with profiling (Trac #14705)
- DWARF debug information support has been significantly improved (Trac #14894, Trac #14779)
- A regression in runtime performance of code involving
newtypes has been fixed (Trac #14936)
4.2. Full details¶
In addition to the highlights listed above, this release resolves a number of other issues, described below.
4.2.1. Compiler¶
- A bug affecting GHC's debug output support (
-g) which resulted in invalid code being generated for string literals (Trac #13868) - Trac #14918, where
Readinstances for types with field names containing#would fail to parse, has been fixed. - Several compiler panics have been resolved (Trac #12158, Trac #15002, Trac #14933, Trac #14959)
- Fix a regression in which derived
Readinstances for record data types with field names ending with#(by way of-XMagicHash) would no longer parse valid output.
4.2.2. Runtime system¶
- A bug causing panics while running programs with retainer profiling
(
-hr) was fixed (Trac #14947)
4.2.3. Template Haskell¶
No changes.
4.2.4. ghc library¶
No changes.
4.2.5. base library¶
- Version bumped to 4.11.1.0 to account for the addition of
GHC.IO.FixIOException - Add the
readFieldHashfunction toGHC.Readwhich behaves likereadField, but for a field that ends with a#symbol.
4.2.6. integer-gmp library¶
- Version bumped to 1.0.2.0 to account for the addition of
powModSecInteger. - Define
powModSecInteger, a "secure" version ofpowModIntegerusing thempz_powm_secfunction.
4.2.7. Build system¶
configurenow takes a--disable-dtraceflag, allowing workaround of Trac #15040.- A bug breaking GHC builds bootstrapped on Darwin has been fixed (Trac #14972)
4.3. 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 | 8.4.3 | 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 | 8.4.3 | Internal compiler library |
| ghc-compact | 0.1.0.0 | Core library |
| ghc-prim | 0.5.2.0 | Core library |
| ghci | 8.4.3 | 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 | 1.2.3.0 | 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 |