Cabal and Cabal-syntax 3.10.1.0 changelog and release notes

Release 3.10.1.0 of cabal now sets the --enable-documentation option by default when running cabal haddock (https://github.com/haskell/cabal/issues/7462). If the new default does not fit your workflow, pass an explicit --disable-documentation option or consider (helping to implement) the other workarounds proposed in https://github.com/haskell/cabal/issues/8725.

This version of cabal introduces support for JS cross-compilation (https://github.com/haskell/cabal/pull/8636). We've seen related Windows segfaults on CI, so please kindly report if you can reproduce either cabal or GHC segfaults when cross-compiling for JS or compiling normally but with any files listed in the js-sources field of a .cabal file.

This release of cabal also fixes a lot of bugs in cabal 3.8.1.0 and not all of the fixes are listed here.

Significant changes

• Add support for the XDG Base Directory Specification #680 #7386

  Cabal/cabal-install now uses the XDG Base Directory Specification to store configuration, caches, and the store. Specifically, $XDG_CONFIG_HOME/cabal stores the configuration file, $XDG_CACHE_HOME/cabal stores downloaded packages and similar, and $XDG_STATE_HOME/cabal mainly contains the store of compiled packages. Further, cabal install will put executables in ~/.local/bin by default.

  The dist/dist-newstyle directories are not affected.

  On Windows, these XDG paths are mapped to other (hopefully) appropriate locations. See the Cabal User Guide for information.

  If the CABAL_DIR environment variable is set, the indicated directory will be used to store all Cabal-related files, as in previous versions.

  Backwards compatibility: If ~/.cabal already exists, this will be interpreted as CABAL_DIR=~/.cabal. This means that upgrading on an existing system already using cabal-install should not cause any change in behaviour. An existing system can be migrated by deleting ~/.cabal (possibly copying ~/.cabal/config to ~/.config/cabal/config first).

• Add PackageInfo_ module #8534

  • Add PackageInfo_ module to embed portable package-related informations (issue #3909)

• Cabal-syntax Add language extensions DeepSubsumption and TypeData #8493

  • adds support for the DeepSubsumption language extension (GHC proposal #511)
  • adds support for the TypeData language extension (GHC proposal #106)

• Add support for GHC 9.4+ -fprof-late flag. #8528

• This adds the new late-toplevel (and its alias late) profiling-detail option which enables -fprof-late-based automatic cost centre annotations for GHCs that support it (earliest is GHC 9.4.1).

Other changes

• Remove "'-main-is' is not portable" check #8646 #8651

  cabal check no longer complains about -main-is flag in ghc-options

• Fix generation of Path_ modules with relocatable #8219 #8220

  The generation of the functions minusFileName and splitFileName are now in the same conditional block as their call, preventing generation of inconsistent Paths_ files where those functions are used but not defined.

• Remove warning on option -threaded when building libraries #774 #8431 #8432

  • Accompanied by option -flink-rts, option -threaded defines the flavour of the ghc RTS library the built library will be linked against. Note that bare ghc does not warn when option -threaded is used for building a library either.
  • Note that the changes require modification of the regression check for issue #774 which can be regarded as a proper test for this PR.

• Add warning about expensive globs #5311 #8441

  • Now cabal check will emit a warning when package uses recursive globs starting at root of the project

• Order extra* stanzas #8458 #8499

  Ensure that extra-src-dirs, extra sources, and extra other modules all are added using ordNub rather than incidentally alphabetized.

• Prepend rather than append extra-prog-path #6304 #8506

  Prepends the extra-prog-path to the system path rather than appending, to allow binaries in the extra path to override defaults.

• don't send non-extant extra-lib-dirs to GHC #6492 #8510

  If an extra-libs-dir does not exist, it does not get sent to ghc, which can error on windows.

• Improve mutually recursive unit identifier error message #8582

  Improves the error message in case of mutually recursive unit identifiers by specifying the name of the identifier, the name of the signature, and a suggestion to check the 'build-depends:' section.

• Specify default exe extension on wasm32 to be .wasm #8633

  Specify default exe extension on wasm32 to be .wasm, following the convention in other WebAssembly toolchains.

• Support js-sources with GHC, not only with GHCJS #8636

  • Take into account js-sources when building library components with GHC
  • Missing support for js-sources in executable components is tracked in #8639

• Tiny refactor of how Cabal handles configure scripts #8648

  None of this is visible downstream

  • Remove needless parameter on one private function.

  • Move another internal function (and ones that only it uses from the same module) to new private module.

• Warn if expected files are omitted from extra-doc-files #3964 #8657

  • Emit a warning if there exist a “changelog” file at the root of the package which is not included in any field.
  • Emit a warning if a “changelog” file at the root of the package is included in a field different from “extra-doc-files” (Cabal spec >= 1.18) or “extra-source-files” (spec < 1.18).

• Disallow GHC <8.0 for #7531 #8715 #8794

  Disallow GHC <8.0 by restricting the version of base that can be used to at least 4.9

• Avoid spurious warnings from -with-rtsopts #4255 #8183

• Do not print "up to date" for commands unless running "cabal build" #4994 #8569

• The configure script of build-type: configure packages now has access to the flag assignment of the package being built via the CABAL_FLAGS and CABAL_FLAG_<flag> environment variables #8564 #8565

• Export pretty printer ppPackageCheck from #8311

• Add check for upper bound on any dependency in cabal check #8291 #8339

• Cabal-syntax Relax language selection parsing in cabal init #8278 #8281