[MacPorts] #65470: gcc12 insists on clang13?!

[MacPorts]

#65470: gcc12 insists on clang13?!
-------------------------+--------------------
  Reporter:  mouse07410  |      Owner:  (none)
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  gcc12       |
-------------------------+--------------------

Comment (by mouse07410):

 > The clang13 dependency is added by the {{{+enable_stdlib_flag}}} variant

 First, could you clarify what that means? What values can one specify for
 that flag?

 This is from Xcode gcc (**not** Macports):
 {{{
 $ gcc --help
 .  .  .
 -stdlib++-isystem <directory>
                           Use directory as the C++ standard library
 include path
   -stdlib=<value>         C++ standard library to use
 .  .  .
 }}}

 This is from Macports gcc11 and gcc12:
 {{{
 $ gcc-mp-11 --help
 .  .  .
   -specs=<file>            Override built-in specs with the contents of
 <file>.
   -std=<standard>          Assume that the input sources are for
 <standard>.
   --sysroot=<directory>    Use <directory> as the root directory for
 headers
                            and libraries.
   -B <directory>           Add <directory> to the compiler's search paths.
   -v                       Display the programs invoked by the compiler.
 .  .  .
 $ gcc-mp-12 --help
 .  .  .
   -specs=<file>            Override built-in specs with the contents of
 <file>.
   -std=<standard>          Assume that the input sources are for
 <standard>.
   --sysroot=<directory>    Use <directory> as the root directory for
 headers
                            and libraries.
   -B <directory>           Add <directory> to the compiler's search paths.
   -v                       Display the programs invoked by the compiler.
 .  .  .
 }}}
 No mentioning of {{{-stdlib}}} at all, let alone any hint what
 could/should be give there.

 This is what "variants" say.
 {{{
 [+]enable_stdlib_flag: Enable stdlib command line flag to select c++
 runtime
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/65470#comment:2>
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