[MacPorts] #59753: gildas @201911b: does not build for the right C++ stdlib (undefined symbols)

[MacPorts]

#59753: gildas @201911b: does not build for the right C++ stdlib (undefined
symbols)
-------------------------+----------------------
  Reporter:  ryandesign  |      Owner:  bardeau
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.6.2
Resolution:              |   Keywords:
      Port:  gildas      |
-------------------------+----------------------

Comment (by bardeau):

 Dear Ryan,

 to have the complete picture, note that there was an attempt to automatize
 the detection of libc++ location (file admin/Makefile.def):

 {{{
 ifeq ($(GAG_COMPILER_CXXKIND),clang++)
   # Apple LLVM: we have to link against libc++. No way to find its correct
   # location, assume default.
   GAG_COMPILER_CXXLIBS = -lc++
 else
   # GNU: we have to link against libstdc++. Find its correct location (it
   # can be at non standard place in case of custom compiler)
   GAG_COMPILER_CXXLIBS = $(shell $(GAG_COMPILER_CXXEXE)
 $(GAG_32BITS_SWITCH) -print-file-name=libstdc++.$(LIB_CXX_EXT))
 endif
 }}}

 This test is useful for those who compile Gildas by themselves (i.e. not
 using MacPorts) like developers or specific users. Unfortunately, as
 quoted above, there is no good solution for the Apple compiler. In
 particular, it accepts the option `--print-file-name=libc++.dylib` but
 fails to returns the full path to its library. This is why the above test
 finally ends by using the default `/usr/lib/libc++.dylib`.

 For the reason explained just above, I would prefer a solution which works
 with or without MacPorts. As the link is the responsibility of the Fortran
 compiler, this solution should use portable options like -L, -l, or just a
 full path like for the GNU case. In second choice, I can try to fix the
 reinplaces to use properly the `@STDCXXLIB@` placeholder.

-- 
Ticket URL: <https://trac.macports.org/ticket/59753#comment:1>
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