You can find more information about why the build failed by switching to the Report navigator and selecting the failed build. You should see why the linker failed.
On reason why this might fail is if you removed Metal support from the Unity player preferences. When doing this, you will still need to add the Metal framework to the Linked Frameworks list, because we need to link against it.
I could fix it following the instruction on your website regarding to add native libraries in the project and setting bitcode to No.
I've created a Unity project (5.6.1f1) and after exporting to Xcode 8.3.3, I get this error:
clang: error: linker command failed with exit code 1 (use -v to see invocation)
I've seen some other topics about it, but nothing works.
Deployment Target is set to 10... and I don't know what to do... Any idea?