[CMake] Where do all the extra clang flags come from in Xcode?

[Paul Smith]

On Sun, 2015-05-17 at 14:43 +0200, Ruslan Baratov via CMake wrote:
> As far as I know extra flags set by Xcode itself. You can use 
> XCODE_ATTRIBUTE_* target properties to enable/disable warnings. This 
> table can be helpful: 
> https://github.com/ruslo/leathers/wiki/List#xcodeclang-table

Thanks for your reply... but I don't quite understand what this table is
telling me.

As mentioned, these builds are performed on build servers running OSX,
where basically the code is retrieved via Git, then cmake is run, then
cmake -build is run (which invokes xcodebuild via the command line), all
using SSH commands from a build control server.  At no time is Xcode
itself invoked.

So, if the properties you describe are Xcode settings that need to be
tweaked then do you know if there is some command-line way to do it,
that I could encode into my build scripts for example?

Thanks!