[MacPorts] #70048: nghttp2 now requires C++20 which introduces a dependency cycle with clang compilers

[MacPorts]

#70048: nghttp2 now requires C++20 which introduces a dependency cycle with clang
compilers
-------------------------------------------------+-------------------------
  Reporter:  conradkun                           |      Owner:  (none)
      Type:  defect                              |     Status:  new
  Priority:  High                                |  Milestone:
 Component:  ports                               |    Version:  2.9.3
Resolution:                                      |   Keywords:
      Port:  nghttp2 curl clang-5.0 clang-6.0    |
  clang-7.0 clang-8.0 clang-9.0 clang-10         |
  clang-11 clang-12 clang-13 clang-14 clang-15   |
  clang-16 clang-17 clang-18                     |
-------------------------------------------------+-------------------------

Comment (by conradkun):

 Thank you for your quick fix. Unfortunately, the bootstrapping of cmake
 does not seem to work on my system. The last lines after trying to install
 `openslide` read:

 {{{
 --->  Fetching archive for cmake
 --->  Attempting to fetch
 cmake-3.29.3_0+universal.darwin_21.arm64-x86_64.tbz2 from
 https://packages.macports.org/cmake
 --->  Attempting to fetch
 cmake-3.29.3_0+universal.darwin_21.arm64-x86_64.tbz2 from
 https://nue.de.packages.macports.org/cmake
 --->  Attempting to fetch
 cmake-3.29.3_0+universal.darwin_21.arm64-x86_64.tbz2 from
 http://mirror.fcix.net/macports/packages/cmake
 --->  Fetching distfiles for cmake
 --->  Attempting to fetch cmake-3.29.3.tar.bz2 from
 https://gitlab.kitware.com/cmake/cmake/-/archive/v3.29.3
 --->  Verifying checksums for cmake
 --->  Extracting cmake
 --->  Applying patches to cmake
 --->  Configuring cmake
 Error: Failed to configure cmake: configure failure: command execution
 failed
 Error: See
 /opt/local/var/macports/logs/_opt_local_var_macports_sources_github
 .com_macports_macports-ports_devel_cmake/cmake/main.log for details.
 Error: Follow https://guide.macports.org/#project.tickets if you believe
 there is a bug.
 Error: Processing of port openslide failed
 }}}

 I am attaching
 `/opt/local/var/macports/logs/_opt_local_var_macports_sources_github
 .com_macports_macports-ports_devel_cmake/cmake/main.log` as well as
 `/opt/local/var/macports/build/_opt_local_var_macports_sources_github
 .com_macports_macports-
 ports_devel_cmake/cmake/work/cmake-3.29.3-x86_64/Bootstrap.cmk/cmake_bootstrap.log`.

 Note that, as you can probably already see, I am using a local git repo to
 call `port sync`. I made sure to pull any changes and sync again before
 trying to install `openslide` again.

-- 
Ticket URL: <https://trac.macports.org/ticket/70048#comment:3>
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