[MacPorts] #69578: abseil @ 20240116.1: Update cxx_standard to 2017

[MacPorts]

#69578: abseil @ 20240116.1: Update cxx_standard to 2017
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 Reporter:  FlyingSamson  |      Owner:  (none)
     Type:  enhancement   |     Status:  new
 Priority:  Normal        |  Milestone:
Component:  ports         |    Version:  2.9.1
 Keywords:                |       Port:  abseil
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 I'm currently trying to package [https://github.com/google/or-tools or-
 tools] in macports (as a dependency to yet another package
 [http://flatcam.org flatcam]).

 The current version of or-tools (and the only one compatible with abseil
 20240116) requires that `absl::string_view` can be assigned to a
 `std::string`, which in turn according to the standard requires that
 `absl::string_view` can be converted to `std::string_view`. However, as
 `std::string_view` is a c++17 feature, this would require an abseil
 version compiled with `-std=c++17`.

 So my question is, wether it would be reasonable to update the standard
 used for building abseil from the current c++14 to c++17?

 Of course I realize that there are quite some ports depending on abseil
 and would be happy to help in testing if these still build with such an
 updated version of abseil if that is of any help.

-- 
Ticket URL: <https://trac.macports.org/ticket/69578>
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