pandoc 1.12.4.2

Those two tarballs are *not* the same. The one you listed is just a straight dump of the github repo, and doesn't, for example, have any of the necessary git submodules checked out, which would result in a broken build (or worse, a successful build but dead-on-arrival binary). The link I posted is a curated binary with the appropriate submodules checked out and irrelevant developer files removed.

If you read the Pandoc installation instructions closely, you'll see that they direct people to the link I originally posted.

Starting from http://johnmacfarlane.net/pandoc/installing.html, go to the instructions for "All platforms" (at the bottom). The second bullet point links to the hackage page here: http://hackage.haskell.org/package/pandoc. At the bottom the hackage page, you can see a link to the curated download tarball: http://hackage.haskell.org/package/pandoc-1.12.4.2/pandoc-1.12.4.2.tar.gz.