ghc

USE flags

• big-endian - Big-endian toolchain support
• binary - Install the binary version directly, rather than using it to build the source version.
• doc - Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally
• elfutils - Enable DWARF-based backtraces using dev-libs/elfutils.
• ghcbootstrap - Internal: Bootstrap GHC from an existing GHC installation.
• ghcmakebinary - Internal: Build binary friendly for redistribution.
• gmp - Use dev-libs/gmp for integer operations (works faster, but an external depend).
• llvm - Pull in dependencies for the sys-devel/llvm codegen backend.
• numa - Enable NUMA thread balancing policy using sys-process/numactl.
• profile - Add support for software performance analysis (will likely vary from ebuild to ebuild)
• test - Enable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)
• unregisterised - Create an unregisterised build in which only the C codegen backend will be available.