[MacPorts] #52537: hatari - fix for build on Snow Leopard without Xcode 4.2

[MacPorts]

#52537: hatari - fix for build on Snow Leopard without Xcode 4.2
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  Reporter:  ken-cunningham-webuse  |      Owner:  macports-tickets@…
      Type:  defect                 |     Status:  new
  Priority:  Normal                 |  Milestone:
 Component:  ports                  |    Version:  2.3.4
Resolution:                         |   Keywords:  haspatch maintainer
      Port:  hatari                 |
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Comment (by mojca):

 I attached some suggestions for improving the patch:
 * Moved the darwin-specific code to a single block and use `replace`
 rather than `delete` and `append`
 * Moved compiler blacklisting inside `if {![variant_isset commandlineapp]}
 {...}`
 * `if { ${os.major} >= 10 }` could of course be replaced by `else`, it's
 up to you. I felt the two things (whether or not to build the gui and
 whether to use `libsdl` or `libsdl2`) were not related in any way. Then,
 if one day gui stops working on 10.6, you could accidentally disable the
 `else` part for 10.6.
 * Added some random minor whitespace changes to comply with "multiples of
 4" rule (I didn't include your changes of lines, but that's not to say
 they shouldn't be there, I just didn't want to make the patch too big).
 I'm not sure whether or not line & whitespace changes warrant a separate
 commit in this case or not. This is usually critical when the whole file
 changes. Just a few minor changes should be fine.

 Personally I would make `gui` an option rather than `commandline` and make
 it default on 10.6+, but that's just "cosmetics" and up to maintainer to
 choose. I guess I would make `libsdl2` default on (at least) 10.7+ and
 `libsdl` as the only option on 10.5 and lower. I don't see any reason to
 keep it as a variant on 10.7+, but again that's up to you to decide, maybe
 the functionality differs or needs more testing? You could keep the
 variant on 10.6 if you want and stay at `libsdl` as the default one.

 These are just a few random thoughts. Please test and provide your final
 decision/patch.

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Ticket URL: <https://trac.macports.org/ticket/52537#comment:18>
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