[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 shpokas):

 Unfortunately, complete removal of CLT with
 {{{
  rm -fr /Library/Developer/CommandLineTools/
 }}}
  and reinstallation from DMG does not work for me.
 I have two Apple Silicon M2 powered machines and on one port compilation
 works fine even with folder
 {{{
 /Library/Developer/CommandLineTools/usr/include/c++
 }}}
  being present but does not work on the other one where after CLT
 reinstallation folder
 {{{
  /Library/Developer/CommandLineTools/usr/include/c++
 }}}
  is not present.

 The port that fails is db48, error is


 {{{
    bc++ -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk
 -arch arm64 ../dist/../cxx/cxx_logc.cpp
    :info:build In file included from ../dist/../cxx/cxx_db.cpp:13:
    :info:build ./db_cxx.h:59:10: fatal error: 'iostream.h' file not found
    :info:build    59 | #include <iostream.h>
    :info:build       |          ^~~~~~~~~~~~
 }}}


 File iostream.h is present on both machines. On the erratic machine:


 {{{
 $ find /Library/Developer/CommandLineTools/ -iname iostream.h | xargs ls
 -l
 -rw-r--r--  1 root  wheel  21722 Apr 25 06:09
 /Library/Developer/CommandLineTools//SDKs/MacOSX14.5.sdk/System/Library/Frameworks/Kernel.framework/Versions/A/Headers/IOKit/stream/IOStream.h
 -rw-r--r--  1 root  wheel  21722 Aug 13 06:56
 /Library/Developer/CommandLineTools//SDKs/MacOSX15.0.sdk/System/Library/Frameworks/Kernel.framework/Versions/A/Headers/IOKit/stream/IOStream.h
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/70750#comment:53>
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