Add ci for DragonFly (disabled for now)

src/ci/docker/disabled/dist-x86_64-dragonfly/Dockerfile

@@ -0,0 +1,36 @@
+FROM ubuntu:16.04
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+  g++ \
+  make \
+  file \
+  curl \
+  ca-certificates \
+  python2.7 \
+  git \
+  cmake \
+  sudo \
+  bzip2 \
+  xz-utils \
+  wget \
+  libssl-dev \
+  bsdtar \
+  pkg-config
+
+
+COPY dist-x86_64-dragonfly/build-toolchain.sh /tmp/
+COPY dist-x86_64-dragonfly/patch-toolchain /tmp/
+RUN /tmp/build-toolchain.sh /tmp/patch-toolchain
+
+COPY scripts/sccache.sh /scripts/
+RUN sh /scripts/sccache.sh
+
+ENV \
+    AR_x86_64_unknown_dragonfly=x86_64-unknown-dragonfly-ar \
+    CC_x86_64_unknown_dragonfly=x86_64-unknown-dragonfly-gcc \
+    CXX_x86_64_unknown_dragonfly=x86_64-unknown-dragonfly-g++
+
+ENV HOSTS=x86_64-unknown-dragonfly
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS --enable-extended
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS

src/ci/docker/disabled/dist-x86_64-dragonfly/build-toolchain.sh

@@ -0,0 +1,120 @@
+#!/bin/bash
+# Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+ARCH=x86_64
+PATCH_TOOLCHAIN=$1
+BINUTILS=2.25.1
+GCC=6.4.0
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  set -x
+}
+
+mkdir binutils
+cd binutils
+
+# First up, build binutils
+curl https://ftp.gnu.org/gnu/binutils/binutils-$BINUTILS.tar.bz2 | tar xjf -
+mkdir binutils-build
+cd binutils-build
+hide_output ../binutils-$BINUTILS/configure \
+  --target=$ARCH-unknown-dragonfly
+hide_output make -j10
+hide_output make install
+cd ../..
+rm -rf binutils
+
+# Next, download the DragonFly libc and relevant header files
+
+URL=http://mirror-master.dragonflybsd.org/iso-images/dfly-x86_64-5.0.0_REL.iso.bz2
+mkdir dragonfly
+curl $URL | bzcat | bsdtar xf - -C dragonfly ./usr/include ./usr/lib ./lib
+
+dst=/usr/local/$ARCH-unknown-dragonfly
+
+mkdir -p $dst/lib
+cp -r dragonfly/usr/include $dst/
+cp dragonfly/usr/lib/crt1.o $dst/lib
+cp dragonfly/usr/lib/Scrt1.o $dst/lib
+cp dragonfly/usr/lib/crti.o $dst/lib
+cp dragonfly/usr/lib/crtn.o $dst/lib
+cp dragonfly/usr/lib/libc.a $dst/lib
+cp dragonfly/usr/lib/libutil.a $dst/lib
+cp dragonfly/usr/lib/libm.a $dst/lib
+cp dragonfly/usr/lib/librt.so.0 $dst/lib
+cp dragonfly/usr/lib/libexecinfo.so.1 $dst/lib
+cp dragonfly/lib/libc.so.8 $dst/lib
+cp dragonfly/lib/libm.so.4 $dst/lib
+cp dragonfly/lib/libutil.so.4 $dst/lib
+cp dragonfly/usr/lib/libpthread.so $dst/lib/libpthread.so
+cp dragonfly/usr/lib/thread/libthread_xu.so.2 $dst/lib/libpthread.so.0
+
+ln -s libc.so.8 $dst/lib/libc.so
+ln -s libm.so.4 $dst/lib/libm.so
+ln -s librt.so.0 $dst/lib/librt.so
+ln -s libutil.so.4 $dst/lib/libutil.so
+ln -s libexecinfo.so.1 $dst/lib/libexecinfo.so
+rm -rf dragonfly
+
+# Finally, download and build gcc to target DragonFly
+mkdir gcc
+cd gcc
+curl https://ftp.gnu.org/gnu/gcc/gcc-$GCC/gcc-$GCC.tar.gz | tar xzf -
+cd gcc-$GCC
+
+# The following three patches are taken from DragonFly's dports collection:
+# https://github.com/DragonFlyBSD/DPorts/tree/master/lang/gcc5
+# The dports specification for gcc5 contains a few more patches, but they are
+# not relevant in this situation, as they are for a language we don't need
+# (e.g. java), or a platform which is not supported by DragonFly (e.g. i386,
+# powerpc64, ia64, arm).
+#
+# These patches probably only need to be updated in case the gcc version is
+# updated.
+
+patch -p0 < $PATCH_TOOLCHAIN
+
+./contrib/download_prerequisites
+
+mkdir ../gcc-build
+cd ../gcc-build
+hide_output ../gcc-$GCC/configure                \
+  --enable-languages=c,c++                       \
+  --target=$ARCH-unknown-dragonfly               \
+  --disable-multilib                             \
+  --disable-nls                                  \
+  --disable-libgomp                              \
+  --disable-libquadmath                          \
+  --disable-libssp                               \
+  --disable-libvtv                               \
+  --disable-libcilkrts                           \
+  --disable-libada                               \
+  --disable-libsanitizer                         \
+  --disable-libquadmath-support                  \
+  --disable-lto
+hide_output make -j10
+hide_output make install
+cd ../..
+rm -rf gcc

src/ci/docker/disabled/dist-x86_64-dragonfly/patch-toolchain

@@ -0,0 +1,23 @@
+--- libstdc++-v3/config/os/bsd/dragonfly/os_defines.h.orig	2015-07-09 16:08:54 UTC
++++ libstdc++-v3/config/os/bsd/dragonfly/os_defines.h
+@@ -29,4 +29,9 @@
+ // System-specific #define, typedefs, corrections, etc, go here.  This
+ // file will come before all others.
+
++#define _GLIBCXX_USE_C99_CHECK 1
++#define _GLIBCXX_USE_C99_DYNAMIC (!(__ISO_C_VISIBLE >= 1999))
++#define _GLIBCXX_USE_C99_LONG_LONG_CHECK 1
++#define _GLIBCXX_USE_C99_LONG_LONG_DYNAMIC (_GLIBCXX_USE_C99_DYNAMIC || !defined __LONG_LONG_SUPPORTED)
++
+ #endif
+--- libstdc++-v3/configure.orig	2016-05-26 18:34:47.163132921 +0200
++++ libstdc++-v3/configure	2016-05-26 18:35:29.594590648 +0200
+@@ -52013,7 +52013,7 @@
+
+     ;;
+
+-  *-freebsd*)
++  *-freebsd* | *-dragonfly*)
+     SECTION_FLAGS='-ffunction-sections -fdata-sections'
+
+