ghc.rb

class Ghc < Formula
  homepage "https://haskell.org/ghc/"
  url "https://downloads.haskell.org/~ghc/7.10.1/ghc-7.10.1-src.tar.xz"
  sha256 "92f3e3d67a637c587c49b61c704a670953509eb4b17a93c0c2ac153da4cd3aa0"

  option "with-tests", "Verify the build using the testsuite."

  if MacOS.version <= :lion
    fails_with :clang do
      cause <<-EOS.undent
        Fails to bootstrap ghc-cabal. Error is:
          libraries/Cabal/Cabal/Distribution/Compat/Binary/Class.hs:398:14:
              The last statement in a 'do' block must be an expression
                n <- get :: Get Int getMany n
      EOS
    end
  end

  resource "binary" do
    if MacOS.version <= :lion
      url "https://downloads.haskell.org/~ghc/7.6.3/ghc-7.6.3-x86_64-apple-darwin.tar.bz2"
      sha256 "f7a35bea69b6cae798c5f603471a53b43c4cc5feeeeb71733815db6e0a280945"
    else
      url "https://downloads.haskell.org/~ghc/7.10.1/ghc-7.10.1-x86_64-apple-darwin.tar.xz"
      sha256 "bc45de19efc831f7d5a3fe608ba4ebcd24cc0f414cac4bc40ef88a04640583f6"
    end
  end

  resource "testsuite" do
    url "https://downloads.haskell.org/~ghc/7.10.1/ghc-7.10.1-testsuite.tar.xz"
    sha256 "33bbdfcfa50363526ea9671c8c1f01b7c5dec01372604d45cbb53bb2515298cb"
  end

  def install
    (buildpath/"mk/build.mk").write(<<-EOS.undent
      V = 0
      GhcLibWays           = v p
      GhcHcOpts            = -O2 -H64m -fasm -Rghc-timing
      GhcStage1HcOpts      = -O2 -H64m -fasm
      GhcStage2HcOpts      = -O2 -H64m -fasm
      GhcLibHcOpts         = -O2 -H64m -fasm
      SRC_HC_OPTS          = -O2 -H64m -fasm
      DYNAMIC_BY_DEFAULT   = NO
      DYNAMIC_GHC_PROGRAMS = NO
      INTEGER_LIBRARY      = integer-simple
    EOS
                                   )

    args = ["--with-hs-cpp-flags=-E -undef -traditional -w",
            "--with-gcc=#{ENV.cc}", "--with-clang=#{ENV.cc}", "--with-ld=ld"]

    resource("binary").stage do
      binary = buildpath/"binary"
      system "./configure", "--prefix=#{binary}", *args
      ENV.deparallelize { system "make", "install" }
      ENV.prepend_path "PATH", binary/"bin"
    end

    system "./configure", "--prefix=#{prefix}", *args
    system "make"

    if build.with? "tests"
      resource("testsuite").stage { buildpath.install Dir["*"] }
      cd "testsuite" do
        system "make", "clean"
        system "make", "CLEANUP=1", "THREADS=#{ENV.make_jobs}", "fast"
      end
    end

    ENV.deparallelize { system "make", "install" }
  end

  test do
    (testpath/"hello.hs").write('main = putStrLn "Hello Homebrew"')
    system "runghc", testpath/"hello.hs"
  end
end