[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 lcvisser):

 I'm still stuck. I got here after trying to install `wget`, which failed
 because `lerc` wouldn't build, failing with various

 {{{
 fatal error: 'algorithm' file not found
    24 | #include <algorithm>
 }}}

 The strange thing is (or at least, the part I don't understand): I can
 build C++ applications just fine. The sample provided in comment:75
 compiles without error, so does all my normal work (although I use CMake,
 which may set some paths differently).

 I too have an apparently stale/incomplete
 `/Library/Developer/CommandLineTools/usr/include/c++/v1`:

 {{{
 % ls -l /Library/Developer/CommandLineTools/usr/include/c++/v1
 total 24
 drwxr-xr-x   3 root  wheel    96 Oct 19  2022 __bit
 drwxr-xr-x   5 root  wheel   160 Oct 19  2022 __charconv
 drwxr-xr-x   9 root  wheel   288 Oct 19  2022 __compare
 drwxr-xr-x  24 root  wheel   768 Oct 19  2022 __concepts
 -rw-r--r--   1 root  wheel  3142 Oct 18  2022 __cxxabi_config.h
 drwxr-xr-x  14 root  wheel   448 Oct 23  2023 __format
 drwxr-xr-x   4 root  wheel   128 Oct 23  2023 __functional
 drwxr-xr-x   3 root  wheel    96 Oct 23  2023 __iterator
 drwxr-xr-x   9 root  wheel   288 Oct 23  2023 __ranges
 drwxr-xr-x   3 root  wheel    96 Oct 23  2023 __utility
 -rw-r--r--   1 root  wheel  7215 Oct 18  2022 cxxabi.h
 }}}

 But again, this is not a problem if I compile my own work.

 Caveat here is that I'm on a corporate machine: I have built MacPorts from
 source and build all ports from source, so I'm used to having to solve the
 occasional problem, but this has me stumped so far. I did get an Xcode
 update pushed last week. I have Xcode 16.0 (16A242d) and clang version
 16.0.0 (clang-1600.0.26.3) on macOS Sonoma 14.5 (23F79)

 {{{
 % clang --version
 Apple clang version 16.0.0 (clang-1600.0.26.3)
 Target: arm64-apple-darwin23.5.0
 Thread model: posix
 InstalledDir:
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
 % xcode-select -p
 /Applications/Xcode.app/Contents/Developer
 }}}

 I don't have administrative rights, but I can ask IT for an admin to do
 things if asked nicely. Should I ask to

 1.  `sudo rm -rf /Library/Developer/CommandLineTools/usr/include/c++/v1` ?
 2. Reinstall CLT?
 3. Reinstall Xcode?
 4. All of the above?

 I also don't mind to rebuild MacPorts and all the ports if that makes any
 sense: I do prefer to solve the issue without having to involve IT.

-- 
Ticket URL: <https://trac.macports.org/ticket/70750#comment:88>
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