[New] Use Clang as C/C++ compiler if we detected it, close #902

.travis.yml

@@ -17,7 +17,10 @@ before_install:
   - $SHELL --version 2> /dev/null || dpkg -s $SHELL 2> /dev/null || which $SHELL
   - curl --version
   - wget --version
+  - clang --version
+  - clang++ --version
   - if [ -n "${SHELLCHECK-}" ]; then sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 575159689BEFB442 && echo 'deb http://download.fpcomplete.com/ubuntu precise main' | sudo tee /etc/apt/sources.list.d/fpco.list && sudo apt-get update && sudo apt-get install stack bc -y && stack setup && stack install ShellCheck && shellcheck --version ; fi
+  - if [ -z "${SHELLCHECK-}" ]; then wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add - && echo -e "deb http://apt.llvm.org/precise/ llvm-toolchain-precise main\ndeb http://apt.llvm.org/precise/ llvm-toolchain-precise-3.8 main" | sudo tee /etc/apt/sources.list.d/clang.list && sudo apt-get update && sudo apt-get install clang-3.8 lldb-3.8 -y --force-yes && sudo ln -sf /usr/bin/clang-3.8 /usr/bin/clang && sudo ln -sf /usr/bin/clang++-3.8 /usr/bin/clang++ && clang --version ; fi
 install:
   - (mkdir /tmp/urchin && cd /tmp/urchin && curl -s "$(curl -s https://registry.npmjs.com/urchin | grep -Eo '"tarball":\s*"[^"]+"' | tail -n 1 | awk -F\" '{ print $4 }')" -O && tar -x -f urchin*)
   - chmod +x /tmp/urchin/package/urchin

nvm.sh

@@ -192,6 +192,10 @@ nvm_rc_version() {
   fi
 }
 
+nvm_clang_version() {
+  clang --version | command awk '{ if ($2 == "version") print $3; else if ($3 == "version") print $4 }' | command sed 's/-.*$//g'
+}
+
 nvm_version_greater() {
   command awk 'BEGIN {
     if (ARGV[1] == "" || ARGV[2] == "") exit(1)
@@ -1854,6 +1858,10 @@ nvm_install_source() {
   elif [ "${NVM_OS}" = 'aix' ]; then
     make='gmake'
   fi
+  if nvm_has "clang++" && nvm_has "clang" && nvm_version_greater_than_or_equal_to nvm_clang_version 3.5 ; then
+    nvm_echo "Clang v3.5+ detected! Use Clang as c/c++ compiler!"
+    MAKE_CXX='CC=clang CXX=clang++'
+  fi
 
   local tar_compression_flag
   tar_compression_flag='z'
@@ -3141,7 +3149,7 @@ nvm() {
         nvm_is_iojs_version nvm_is_alias \
         nvm_ls_remote nvm_ls_remote_iojs nvm_ls_remote_index_tab \
         nvm_ls nvm_remote_version nvm_remote_versions \
-        nvm_install_binary \
+        nvm_install_binary nvm_clang_version \
         nvm_get_mirror nvm_get_download_slug nvm_download_artifact \
         nvm_install_source nvm_check_file_permissions \
         nvm_print_versions nvm_compute_checksum nvm_checksum \

test/fast/Unit tests/nvm_clang_version

@@ -0,0 +1,62 @@
+#!/bin/sh
+
+cleanup () {
+  unset -f die
+}
+
+die () { echo -e "$@" ; cleanup ;  exit 1; }
+
+if type "clang" > /dev/null 2>&1 ; then
+  clang_exec="$(type "clang")"
+  sudo rm -rf "${clang_exec}"
+fi
+if type "clang++" > /dev/null 2>&1 ; then
+  clangxx_exec="$(type "clang++")"
+  sudo rm -rf "${clangxx_exec}"
+fi
+
+NVM_ENV=testing \. ../../../nvm.sh
+
+clang() {
+  if [ "$1" = "--version" ]; then
+    echo "${VERSION_MESSAGE}"
+  fi
+}
+
+assert_version_is() {
+  if [ "${1}" != "${2}" ]; then
+    die "Expected ${2}, got ${1}, origin version message:\n${VERSION_MESSAGE}"
+    return 1
+  fi
+}
+
+CLANG_VERSION_ON_DEBIAN_JESSIE="Debian clang version 3.5.0-10 (tags/RELEASE_350/final) (based on LLVM 3.5.0)
+Target: x86_64-pc-linux-gnu
+Thread model: posix"
+
+CLANG_VERSION_ON_UBUNTU_TRUSTY="Ubuntu clang version 3.4-1ubuntu3 (tags/RELEASE_34/final) (based on LLVM 3.4)
+Target: x86_64-pc-linux-gnu
+Thread model: posix"
+
+CLANG_VERSION_ON_ARCHLINUX="clang version 3.9.0 (tags/RELEASE_390/final)
+Target: x86_64-unknown-linux-gnu
+Thread model: posix
+InstalledDir: /usr/sbin"
+
+CLANG_VERSION_ON_FREEBSD="FreeBSD clang version 3.4.1 (tags/RELEASE_34/dot1-final 208032) 20140512
+Target: x86_64-unknown-freebsd10.3
+Thread model: posix"
+
+VERSION_MESSAGE="${CLANG_VERSION_ON_DEBIAN_JESSIE}"
+assert_version_is "$(nvm_clang_version)" "3.5.0"
+
+VERSION_MESSAGE="${CLANG_VERSION_ON_UBUNTU_TRUSTY}"
+assert_version_is "$(nvm_clang_version)" "3.4"
+
+VERSION_MESSAGE="${CLANG_VERSION_ON_ARCHLINUX}"
+assert_version_is "$(nvm_clang_version)" "3.9.0"
+
+VERSION_MESSAGE="${CLANG_VERSION_ON_FREEBSD}"
+assert_version_is "$(nvm_clang_version)" "3.4.1"
+
+cleanup