[MacPorts] #59807: libcxx needs a method to bootstrap to the +emulated_tls variant

[MacPorts]

#59807: libcxx needs a method to bootstrap to the +emulated_tls variant
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  Reporter:  fvaccari  |      Owner:  jeremyhu
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.2
Resolution:            |   Keywords:  snowleopard
      Port:  libcxx    |
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Comment (by kencu):

 currently `libcxx` has the default variant of +`emulated_tls` if the
 toolchain parts are in place to build it.

 But I wonder if we might be able to make the `+emulated_tls` variant a
 default variant the port is being installed from the buildbot. Then we
 could skip the bootstrapping issues that way.

 The `apple_gcc42` port has a standard install of no variants, but to get
 to that standard install, you first need to install the bootstrap variant,
 and then do the manual step of reinstalling it without the bootstrap
 variant. But this means that users who get the port from the buildbot get
 the fully functional version from the buildbot, skipping the bootstrap
 variant entirely.

 Perhaps some variation on that logic might work here too... and maybe the
 same for the `ld64-latest` variant of `ld64` as well, which currently has
 the same manual bootstrapping step.

-- 
Ticket URL: <https://trac.macports.org/ticket/59807#comment:6>
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