aws-sdk-cpp: Enable on Darwin systems

[matthewbauer]

Motivation for this change

aws-sdk-cpp was broken because libuuid wasn't available. Using libossp-uuid on OS X works great.

Things done

• Tested using sandboxing
  (nix.useSandbox on NixOS,
  or option build-use-sandbox in nix.conf
  on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • Linux
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

libuuid can be provided by libossp_uuid.

[mention-bot]

@matthewbauer, thanks for your PR! By analyzing the history of the files in this pull request, we identified @edolstra, @copumpkin and @pikajude to be potential reviewers.

[copumpkin]

I swear this was used at some point, but I can't find anything now. I wonder where it went!

[copumpkin]

Either way, if you're going to get rid of this, I'd get rid of the associated Nix file as well.

[matthewbauer]

Oops that shouldn't be in here! I'll open a separate pr for that and get rid of it here.

[Et7f3]

Why was it reverted by ef65353 ?

It break darwin.opencflite:

$ nix build .#darwin.opencflite
error: value is null while a set was expected

       at /nix/store/bp70yjxsfkcamiq5m19phbkjk9rnrm61-source/pkgs/os-specific/darwin/opencflite/default.nix:12:37:

           11|
           12|   configureFlags = [ "--with-uuid=${libuuid.dev}" ];
             |                                     ^
           13|   buildInputs = [ icu tzdata.dev ];
(use '--show-trace' to show detailed location information)

@LnL7

I see the official implementation is open source https://github.com/apple-oss-distributions/xnu/blob/5c2921b07a2480ab43ec66f5b9e41cb872bc554f/libkern/uuid/uuid.c