[Haskell] ANNOUNCE: GHC version 7.4.1

Ian Lynagh igloo at earth.li
Thu Feb 2 21:51:13 CET 2012

    The (Interactive) Glasgow Haskell Compiler -- version 7.4.1

The GHC Team is pleased to announce a new major release of GHC, 7.4.1.

Here are some of the highlights of the 7.4 branch since 7.2 and 7.0:

  * The Num class no longer has Eq or Show superclasses.

  * There is a new feature Safe Haskell (-XSafe, -XTrustworthy, -XUnsafe).
    The design has changed since 7.2.

  * There is a new feature kind polymorphism (-XPolyKinds).
    A side-effect of this is that, when the extension is not enabled, in
    certain circumstances kinds are now defaulted to * rather than being

  * There is a new feature constraint kinds (-XConstraintKinds).

  * It is now possible to give any sort of declaration at the ghci prompt.
    For example, you can now declare datatypes within ghci.

  * The profiling and hpc implementations have been merged and overhauled.
    Visible changes include renaming of profiling flags, and a new
    semantics for the cost-centre stacks (which should in most cases
    result in more useful and intuitive profiles). The +RTS -xc flag now
    also gives a stack trace.

  * It is now possible to write compiler plugins.

  * DPH support has been significantly improved.

  * There is now preliminary support for registerised compilation using
    LLVM on the ARM platform.

Full release notes are here:


How to get it

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