[MacPorts] #54900: libgcc @7.2.0: fatal error: bits/regex_scanner.tcc: No such file or directory

[MacPorts]

#54900: libgcc @7.2.0: fatal error: bits/regex_scanner.tcc: No such file or
directory
---------------------------+------------------------
  Reporter:  cjones051073  |      Owner:
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.4.1
Resolution:                |   Keywords:  highsierra
      Port:  libgcc        |
---------------------------+------------------------

Comment (by jwhowarth):

 I believe you are running into
 [https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81797] which occurs on APFS
 volumes. The issue apparent be the fine granularity of the new filesystem
 breaking the time stamping scheme used in the install-headers section of
 libstdc++-v3/include/Makefile.in (which is based on the existence of
 directories and not their population state). The workaround is to use the
 change...


 {{{
 diff -uNr gcc-7.2.0.orig/libstdc++-v3/include/Makefile.in
 gcc-7.2.0/libstdc++-v3/include/Makefile.in
 --- gcc-7.2.0.orig/libstdc++-v3/include/Makefile.in     2017-07-25
 14:05:07.000000000 -0400
 +++ gcc-7.2.0/libstdc++-v3/include/Makefile.in  2017-09-02
 12:22:08.000000000 -0400
 @@ -1764,6 +1764,8 @@
  @GLIBCXX_HOSTED_TRUE at install-data-local: install-headers
  @GLIBCXX_HOSTED_FALSE at install-data-local: install-freestanding-headers

 +.NOTPARALLEL: install-headers
 +
  # This is a subset of the full install-headers rule.  We only need
 <ciso646>,
  # <cstddef>, <cfloat>, <limits>, <climits>, <cstdint>, <cstdlib>, <new>,
  # <typeinfo>, <exception>, <initializer_list>, <cstdalign>, <cstdarg>,
 }}}

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Ticket URL: <https://trac.macports.org/ticket/54900#comment:9>
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