build clang

build.sh

#!/bin/bash -ex

CC="clang"
CXX="clang++"

SRCTOP=$(readlink -f ${PWD})
INSTALL=${SRCTOP}/install
if [[ ! -d ${SRCTOP}/llvm ]]; then
    echo Expected to find the source in ${SRCTOP}/llvm but it is missing
    exit 3
fi

HAS_AVX=$(egrep -c '^flags.*\bavx\b' /proc/cpuinfo)

#ignore: covered by -march=native
if [[ ${HAS_AVX} != 0 ]]; then
    AVX_FLAG="-mavx"
fi

build()
{
    mkdir -p obj
    cd obj
    cmake -G Ninja \
        -DCMAKE_BUILD_TYPE=Release \
        -DCMAKE_C_COMPILER=${CC} \
        -DCMAKE_CXX_COMPILER=${CXX} \
        -DCMAKE_CXX_FLAGS="-march=native -O3" \
        -DCMAKE_C_FLAGS="-march=native -O3" \
        -DCMAKE_INSTALL_PREFIX=${INSTALL} \
        -DCMAKE_BUILD_WITH_INSTALL_RPATH=TRUE \
        -DLLVM_USE_LINKER=gold \
        -DLLVM_TARGETS_TO_BUILD="X86" \
        -DLLVM_PARALLEL_LINK_JOBS:INT=6 \
        ${SRCTOP}/llvm 

    \time ninja
    \time ninja install
}

build 2>&1 | tee build.log
du -hs ${INSTALL}

clone_clang.sh

#!/bin/bash -ex

git clone https://github.com/llvm-mirror/llvm/
git clone -q https://github.com/llvm-mirror/clang/ llvm/tools/clang &
git clone -q https://github.com/llvm-mirror/compiler-rt/ llvm/projects/compiler-rt & 
git clone -q https://github.com/llvm-mirror/libcxx/ llvm/projects/libcxx & 
git clone -q https://github.com/llvm-mirror/libcxxabi/ llvm/projects/libcxxabi & 

wait