[MacPorts] #63018: Failed to build libgcc9 on Mac OS X 10.7.5

[MacPorts]

#63018: Failed to build libgcc9 on Mac OS X 10.7.5
-----------------------+---------------------
  Reporter:  YesNo801  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.7.1
Resolution:            |   Keywords:  libgcc9
      Port:  libgcc9   |
-----------------------+---------------------

Comment (by kencu):

 Yeah, that's it. At least on 10.7.5, everything is deleted from the
 destroot by the portfile. You can prove this by leaving a little turd
 behind in the libdir, by adding this to the gcc9 Portfile:
 {{{
     post-destroot {

         # Create temporary lib dir
         file mkdir ${destroot}${prefix}/lib/libgcc.merged
 +         system "echo ${subport} leaves a turd behind >
 ${destroot}${prefix}/lib/libgcc.merged/README"

         # Loop over the specific libs provided by this port
         foreach dylib ${install_dylibs} {
 }}}

 which then installs libgcc9:
 {{{
 $ port -v installed libgcc9
 The following ports are currently installed:
   libgcc9 @9.4.0_0 (active) requested_variants='' platform='darwin 11'
 archs='x86_64' date='2021-06-10T00:21:17-0700'
 }}}
 and leaves behind our turd:
 {{{
 $ port contents libgcc9
 Port libgcc9 contains:
   /opt/local/lib/libgcc/README
 }}}

 and then no doubt gcc9 will install without issues if we want it to.
 That'll be next.

 The question is -- what is libgcc9 installing on 10.8 through 11.0? Why is
 10.7 different?

-- 
Ticket URL: <https://trac.macports.org/ticket/63018#comment:8>
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