Phase Out Xcode Dependency GSOC Project Update

[Clemens Lang]

Hi Sat,

On Tue, Jul 16, 2019 at 10:57:41PM +0700, Satryaji Aulia wrote:
> We haven't discussed whether or not the `xcodeversion` PortGroup
> should be included. We also **restrict** Xcode in tracemode if not
> needed. An exception if is CLT isn't installed.

The xcodeversion PortGroup says it determines the version of Xcode from
/usr/bin/xcodebuild -version. Running that with DEVELOPER_DIR set to the
command line tools seems to fail:

$> DEVELOPER_DIR=/Library/Developer/CommandLineTools xcodebuild -version
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

As a consequence I would say that the xcodeversion PortGroup should set
use_xcode yes. I am aware that we have previously used this to blacklist
specific compiler versions installed by older Xcode versions due to know
problems, but this should nowadays be seldom since we introduced
compiler.blacklist.

HTH,
Clemens