Upgrade GCC to 5.2.0 for Windows x86 and x86_64

This patch does a few things

- Moved GHC x86 to MinGW-w64 (Using Awson's patch)
- Moves Both GHCs to MSYS2 toolchains
- Completely removes the dependencies on the git tarball repo
  - Downloads only the required tarball for the architecture for
    which we are building
  - Downloads the perl tarball is missing as well
  - Fixed a few bugs in the linker to fix tests on Windows

The links currently point to repo.msys2.org and GitHub, it might be
more desirable to mirror them on
http://downloads.haskell.org/~ghc/mingw/ as with the previous patch
attempt.

For more details on what the MSYS2 packages I include see #10726
(Awson's comment). but it should contain all we need
and no python or fortran, which makes the uncompressed tar a 1-2
hundreds mb smaller.

The `GCC 5.2.0` in the package supports `libgcc` as a shared library,
this is a problem since
when compiling with -shared the produced dll now has a dependency on
`libgcc_s_sjlj-1.dll`.
To solve this the flag `-static-libgcc` is now being used for all GCC
calls on windows.

Test Plan:
./validate was ran both on x86 and x86_64 windows and compared against
the baseline.

A few test were failing due to Ld no longer being noisy. These were
updated.

The changes to the configure script *should* be validated by the build
bots for the other platforms before landing

Reviewers: simonmar, awson, bgamari, austin, thomie

Reviewed By: thomie

Subscribers: #ghc_windows_task_force, thomie, awson

Differential Revision: https://phabricator.haskell.org/D1123

GHC Trac Issues: #10726, #9014, #9218, #10435

1 files changed, 0 insertions, 13 deletions

diff --git a/tarballs b/tarballs
deleted file mode 100644
index 5a7b72d5b8..0000000000
--- a/tarballs
+++ /dev/null
@@ -1,13 +0,0 @@
-# The format of the lines in this file is:
-#   localpath    remotepath
-# where
-#   * localpath is where to put the repository in a checked out tree,
-#   * remotepath is where the tarball is in the central repository.
-#
-# Lines that start with a '#' are comments.
-mingw/binutils-2.19.1-mingw32-bin.tar.gz    ghc-tarballs/binutils-2.19.1-mingw32-bin.tar.gz
-mingw/gcc-core-3.4.5-20060117-3.tar.gz      ghc-tarballs/gcc-core-3.4.5-20060117-3.tar.gz
-mingw/mingw-runtime-3.14.tar.gz             ghc-tarballs/mingw-runtime-3.14.tar.gz
-mingw/w32api-3.13-mingw32-dev.tar.gz        ghc-tarballs/w32api-3.13-mingw32-dev.tar.gz
-libffi/tarball/libffi-3.0.8.tar.gz          ghc-tarballs/libffi-3.0.8.tar.gz
-