[MacPorts] #67977: gtk4 uses Linux flags on Mac which breaks the build

[MacPorts]

#67977: gtk4 uses Linux flags on Mac which breaks the build
---------------------------+----------------------
  Reporter:  barracuda156  |      Owner:  mascguy
      Type:  defect        |     Status:  assigned
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.8.1
Resolution:                |   Keywords:
      Port:  gtk4          |
---------------------------+----------------------

Comment (by mascguy):

 `-export_dynamic` isn't Linux-specific. From the man page for `ld`:

 {{{
 -export_dynamic
     Preserves all global symbols in main executables during LTO. Without
 this option, Link Time Optimization is allowed to inline
     and remove global functions. This option is used when a main
 executable may load a plug-in which requires certain symbols from
     the main executable.
 }}}

 However, a quick Google search suggests that it's not necessarily
 supported with GCC.

 Just as importantly, `gtk4` doesn't build for macOS 10.6 and earlier. And
 to answer the obvious question: No, we don't have an ETA, relative to
 supporting 10.6.

 https://ports.macports.org/port/gtk4/details/

-- 
Ticket URL: <https://trac.macports.org/ticket/67977#comment:1>
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