[MacPorts] #69975: re2 at 2024-04-01_2: fails to build on macOS 10.12/Xcode 9.2 due to <optional> not found in abseil headers

[MacPorts]

#69975: re2 at 2024-04-01_2: fails to build on macOS 10.12/Xcode 9.2 due to <optional>
not found in abseil headers
---------------------+-------------------------
 Reporter:  andlabs  |      Owner:  herbygillot
     Type:  defect   |     Status:  assigned
 Priority:  Normal   |  Milestone:
Component:  ports    |    Version:  2.9.3
 Keywords:           |       Port:  re2
---------------------+-------------------------
 Not sure if this is an issue with re2 or with abseil, but re2 is including
 abseil's std::optional improvements and it's failing to build on macOS
 10.12 with Xcode 9.2:

 {{{
 :info:build /usr/bin/clang++ -Dre2_EXPORTS
 -I/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01
 -isystem /opt/local/include -pipe -Os -DNDEBUG -I/opt/local/include
 -stdlib=libc++ -std=gnu++1z -arch x86_64 -mmacosx-version-min=10.12 -fPIC
 -MD -MT CMakeFiles/re2.dir/re2/compile.cc.o -MF
 CMakeFiles/re2.dir/re2/compile.cc.o.d -o
 CMakeFiles/re2.dir/re2/compile.cc.o -c
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/compile.cc
 :info:build /usr/bin/clang++ -Dre2_EXPORTS
 -I/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01
 -isystem /opt/local/include -pipe -Os -DNDEBUG -I/opt/local/include
 -stdlib=libc++ -std=gnu++1z -arch x86_64 -mmacosx-version-min=10.12 -fPIC
 -MD -MT CMakeFiles/re2.dir/re2/bitmap256.cc.o -MF
 CMakeFiles/re2.dir/re2/bitmap256.cc.o.d -o
 CMakeFiles/re2.dir/re2/bitmap256.cc.o -c
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/bitmap256.cc
 :info:build In file included from
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/filtered_re2.cc:5:
 :info:build In file included from In file included from
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/bitstate.cc:28:
 :info:build
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/filtered_re2.hIn
 file included from
 :/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/prog.h:2922:
 :info:build :
 :info:build In file included from In file included from
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/re2.h/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_re2/re2/work/re2-2024-04-01/re2/re2.h::224224:
 :info:build :
 :info:build /opt/local/include/absl/types/optional.h:43:10: fatal error:
 'optional' file not found
 :info:build /opt/local/include/absl/types/optional.h:43:10: fatal error:
 'optional' file not found
 :info:build #include <optional>  // IWYU pragma: export
 :info:build          ^~~~~~~~~~
 :info:build #include <optional>  // IWYU pragma: export
 :info:build          ^~~~~~~~~~
 }}}

 Is this a case of needing MacPorts libc++? This only started happening
 with this version; I'd have assumed it would show up sooner, *and* that
 <optional> would be in system libc++ if it supports `c++1z`...

 I have no variants set on either abseil or re2.

-- 
Ticket URL: <https://trac.macports.org/ticket/69975>
MacPorts <https://www.macports.org/>
Ports system for macOS