Issue description

When trying to build dmd it works with sandbox mode disabled but if it's enabled or set to relaxed building the package fails quite soon after start because of a failed link.

ld: file not found: /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation ld: file not found: /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation clang-5.0: error: clang-5.0linker command failed with exit code 1 (use -v to see invocation):

Steps to reproduce

Comment out the lines doCheck = true and inherit phobosUnittests in pkgs/development/compilers/dmd/default.nix and start build with nix-build -A dmd and make sure sandbox mode is enabled.

Technical details

Please run nix-shell -p nix-info --run "nix-info -m" and paste the
results.

• system: "x86_64-darwin"
• host os: Darwin 17.5.0, macOS 10.13.4
• multi-user?: yes
• sandbox: relaxed
• version: nix-env (Nix) 2.0.2
• channels(root): "nixpkgs-18.03-darwin"
• channels(thomad): "nixpkgs-18.03-darwin"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixpkgs