[MacPorts] #67790: ht: Fix arm64 compilation

[MacPorts]

#67790: ht: Fix arm64 compilation
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  Reporter:  rdoeffinger  |      Owner:  (none)
      Type:  defect       |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:  arm64 haspatch
      Port:  ht           |
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Comment (by jmroot):

 This will change the struct layout, which would break binary compatibility
 with anything using it, but fortunately it looks like this header is not
 intended to be used by anything but this program.

 The packed declaration is presumably to avoid wasting memory with a "hole"
 in the struct due to alignment. It's traditional to declare struct members
 in order from largest to smallest alignment to avoid this problem while
 also avoiding unaligned accesses, which are usually less efficient even if
 the architecture allows them.

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Ticket URL: <https://trac.macports.org/ticket/67790#comment:3>
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