Hey Devs,

I'm having trouble building the head of the ghc-8.6 branch (`26a7f850d1`) on my Arch Linux machine. The essence of the error is this as follows, though the full result of make (to the point of error) is attached.

```

Configuring template-haskell-2.14.0.0...

ghc-cabal: Encountered missing dependencies:

ghc-boot-th ==8.6.* && ==8.7

```

The output of configure is as follows:

```

----------------------------------------------------------------------

Configure completed successfully.

Building GHC version : 8.7.20180730

Git commit id : 26a7f850d15b91ad68d1e28d467faba00bb79144

Build platform : x86_64-unknown-linux

Host platform : x86_64-unknown-linux

Target platform : x86_64-unknown-linux

Bootstrapping using : /usr/bin/ghc

which is version : 8.4.3

Using (for bootstrapping) : gcc

Using gcc : gcc

which is version : 8.1.1

Building a cross compiler : NO

Unregisterised : NO

hs-cpp : gcc

hs-cpp-flags : -E -undef -traditional

ar : ar

ld : ld.gold

nm : nm

libtool : libtool

objdump : objdump

ranlib : ranlib

windres :

dllwrap :

genlib :

Happy : /home/ara/.local/bin/happy (1.19.9)

Alex : /usr/bin/alex (3.2.4)

Perl : /usr/bin/perl

sphinx-build : /usr/bin/sphinx-build

xelatex : /usr/bin/xelatex

Using LLVM tools

clang : clang

llc :

opt :

HsColour : /usr/bin/HsColour

Tools to build Sphinx HTML documentation available: YES

Tools to build Sphinx PDF documentation available: YES

----------------------------------------------------------------------

```

Any help would be most appreciated.

Best,
_ara