[MacPorts] #67637: Universal builds with clang erroneously require clang itself to be universal

[MacPorts]

#67637: Universal builds with clang erroneously require clang itself to be
universal
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  Reporter:  fhgwright  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  base       |    Version:  2.8.1
Resolution:             |   Keywords:
      Port:             |
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Comment (by kencu):

 This is not a bug, the universal build of clang and LLVM was allowed to
 mean clang itself was universal on purpose, not as an oversight of some
 kind.

 For one, clang and LLVM provide several libraries that other ports link
 against, and they do need to be universal at times. So the universal clang
 is needed there.

 For another, real universal on 10.5 and 10.6 was needed, as some 10.5 and
 10.6 installations are unable to run the 64 bit versions.

 our gcc builds are "fake universal" and by that we mean that only the
 relevant library parts are actually universal. So the gcc builds can build
 universal software, but are not themselves universal. This has caused a
 fair bit of headache at times over the years, but it can be lived with.

 Varoius folks have stumbled across the fact that a non-universal
 clang/llvm can build universal software over the years, me included -- in
 the end, they have always decided that the best thing is to have
 clang/llvm actually be universal.

 Of course, that could change, and could be worked around -- for no
 particular benefit. We are currently discussing doing the exact opposite
 move with gcc, and making it "real universal" instead of "fake universal"
 due to headaches we are having with, for example, gcc10-bootstrap and
 other gcc versions.

-- 
Ticket URL: <https://trac.macports.org/ticket/67637#comment:3>
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