[m-dev.] Almost ready to merge the update_boehm branch

[Paul Bone]

I'm almost ready to merge the upgrade_boehm branch.

Once it's merged you will need to use the prepare.sh script to prepare your
checkout before running configure (see below).  I will now run some
performance tests (for curiosity's sake) and then I'm ready to merge this
into master.  Now is your chance to check my work for anything I may have
missed, compiler/notes/upgrade_boehm_gc.html contains a summary of how I've
set this up and is a good place to start.  Note that the general plan of how
to set this up has already been reviewed, I'd rather not go back and forth
on that.

If anyone would like to test it you can do the following.  This is also a
test that this works from a fresh checkout.

    $ git clone https://github.com/Mercury-Language/mercury.git
    Cloning into 'mercury'...
    remote: Counting objects: 157849, done.
    remote: Compressing objects: 100% (371/371), done.
    remote: Total 157849 (delta 129), reused 0 (delta 0), pack-reused 157478
    Receiving objects: 100% (157849/157849), 79.24 MiB | 1.05 MiB/s, done.
    Resolving deltas: 100% (128159/128159), done.
    Checking connectivity... done.

Switch branches:

    $ cd mercury
    $ git branch upgrade_boehm origin/upgrade_boehm
    Branch upgrade_boehm set up to track remote branch upgrade_boehm from origin.
    $ git checkout upgrade_boehm
    Switched to branch 'upgrade_boehm'
    Your branch is up-to-date with 'origin/upgrade_boehm'.

The new prepare.sh script will fetch/update the boehm_gc and libatomic_ops
repositories.  It also runs aclocal -I m4 and autoconf.

    $ ./prepare.sh
    Cloning into 'boehm_gc'...
    remote: Counting objects: 18928, done.
    remote: Compressing objects: 100% (44/44), done.
    remote: Total 18928 (delta 22), reused 0 (delta 0), pack-reused 18884
    Receiving objects: 100% (18928/18928), 10.70 MiB | 995.00 KiB/s, done.
    Resolving deltas: 100% (14986/14986), done.
    Checking connectivity... done.
    Submodule path 'boehm_gc': checked out
    'a16bf06bdc61e07ae65b431bcce9227f4e2b1f63'
    Cloning into 'libatomic_ops'...
    remote: Counting objects: 4638, done.
    remote: Compressing objects: 100% (2/2), done.
    remote: Total 4638 (delta 0), reused 0 (delta 0), pack-reused 4636
    Receiving objects: 100% (4638/4638), 1.91 MiB | 508.00 KiB/s, done.
    Resolving deltas: 100% (3039/3039), done.
    Checking connectivity... done.
    Submodule path 'libatomic_ops': checked out
    'f7549252397e1b315773a5755f0d8fd1c9a284d4'

Now you're good to go with ./configure



-- 
Paul Bone