> On 21 Jun 2019, at 00:25, Robert Pluim <rpluim@gmail.com> wrote:
> 
>    VanL> I take out-of tree to mean the downloaded distribution without any git stuff that was announced on gmane.
> 
> Say your emacs source code is in 'emacs-26'.
> 
> An in-tree build is: 
> cd emacs-26; configure; make
> 
> An out-of tree build is 
> 
> mkdir emacs-26-build; cd emacs-26-build; ../emacs-26/configure; make
> 
> Both should work, especially from release tarballs.

That explains it. Thanks.

The inability to find 'macuvs.h' could be due to MacPort's gcc environment.  The 'clang' build finds it.