[MacPorts] #70750: C++ headers are not found after updating to CLTs version 16.0

[MacPorts]

#70750: C++ headers are not found after updating to CLTs version 16.0
-----------------------+----------------------------
  Reporter:  SaintBol  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:  sequoia sonoma
      Port:            |
-----------------------+----------------------------

Comment (by hnarayanan):

 I am in the same boat as many other people (M1 Max from 2021).

 {{{
 [~] xcode-select -p
 /Applications/Xcode.app/Contents/Developer
 }}}

 I have tried to:

 1. Delete Command Line Tools (with {{{sudo rm -fr
 /Library/Developer/CommandLineTools}}}) and reinstall via {{{xcode-select
 --install}}}, and this installed a version that was deemed too old and
 needed to be updated first (presumably from 15.x to 16.0).
 2.Delete Command Line Tools and reinstall via {{{xcode-select
 --install}}}, and this installed a version from the DMG (16.0) on the
 Apple Developer Website.

 Both of these don't do anything, and I still end up with the same error on
 the most basic C++ program.

 {{{
 [~] clang++ -o main main.cc
 main.cc:1:9: fatal error: 'iostream.h' file not found
     1 | #include<iostream.h>
       |         ^~~~~~~~~~~~
 1 error generated.
 }}}

 I feel the output of {{{xcode-select -p}}} implies none of this is being
 used at all in my case?

-- 
Ticket URL: <https://trac.macports.org/ticket/70750#comment:78>
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