Dropping recommendation to install system headers / command line tools

[Jan Stary]

On Jul 03 21:21:36, jeremyhu at macports.org wrote:
> base currently outputs a warning if system headers are not installed.  I modified the warning a few months ago when I improved our support for building against SDKs, and it now reads:
> 
>    Warning: System headers do not appear to be installed. Most ports should build corectly, but if you experience problems due to a port depending on system headers, please file a ticket at https://trac.macports.org.
>    Warning: You can install them as part of the Xcode Command Line Tools package by running `xcode-select --install'.
> 
> How many developers are using Xcode with the system headers installed vs without system headers?

It's a UNIX system. I want it to have /usr/include/unistd.h etc.

> If you are using system headers (currently installed through the CLTools package and through similar means on older OS versions), can you please indicate why you are unable to use an SDK?

The question seems to imply that I should _not_ use system headers
unless I absolutely have to. That puzzles me.

> I haven't seen any tickets about issues when using an SDK over system headers,
> and the only issue I'm aware of is with gcc ports (which is an upstream bug and mostly worked around).

Even if failing to build a compiler is "the only issue", it's a pretty major one, no?
GNU does not even consider it a proper bug yet (it's UNCONFORMED):
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79885

> I'd like to remove this warning in order to indicate that building against an SDK is now a more supported configuration.  IMO, it should be the *preferred* configuration

Why?

> as it avoids /usr/local/{include,lib} contamination.  What are the thoughts on this?

What contamination? I don't even have /usr/local/

	Jan