[MacPorts] #52554: libomp @3.9.0_1 won't build on Snow Leopard, Mac OS X 10.6.8, because of missing llvm-lit?

[MacPorts]

#52554: libomp @3.9.0_1 won't build on Snow Leopard, Mac OS X 10.6.8, because of
missing llvm-lit?
------------------------+--------------------------------
  Reporter:  ballapete  |      Owner:  macports-tickets@…
      Type:  defect     |     Status:  closed
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.3.4
Resolution:  wontfix    |   Keywords:
      Port:  libomp     |
------------------------+--------------------------------

Comment (by kencu):

 Wait a sec -- what this block does is : if the user is set to `libstdc++`,
 force the `-stdlib=libc++` flag onto the build line to make it build.
 {{{
 if {${os.platform} eq "darwin" && ${configure.cxx_stdlib} eq "libstdc++"}
 {
                 if {${os.major} <= 12} {
                     # kmp_alloc.c includes <atomic> but libc++ is not the
 default on these systems
                     # see https://trac.macports.org/ticket/52554
                     configure.cflags-appends -stdlib=libc++
                 }
 }
 }}}

 It might build. But I would argue that now we don't know where the heck we
 are. What is linked to what? You're mixing standard libraries, and only
 grief can follow that.

 A proper fix would appear to be to first make sure the user is set up to
 use libc++, and if so, add the flag if it is still needed (on some builds
 it is) -- not to force the flag when it is not appropriate, just to make
 it build.

--
Ticket URL: <https://trac.macports.org/ticket/52554#comment:17>
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