[MacPorts] #70087: plplot fails to build: cc1: error: argument to '-O' should be a non-negative integer, 'g', 's', 'z' or 'fast'

[MacPorts]

#70087: plplot fails to build: cc1: error: argument to '-O' should be a non-
negative integer, 'g', 's', 'z' or 'fast'
---------------------------+--------------------
  Reporter:  barracuda156  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.9.3
Resolution:                |   Keywords:
      Port:  plplot        |
---------------------------+--------------------

Comment (by barracuda156):

 Replying to [comment:4 ryandesign]:
 > Replying to [comment:1 barracuda156]:
 > > I do not see where the source adds this flag btw.
 >
 > It's right there in cmake/modules/aqt.cmake:
 >
 > {{{
 >     set(aqt_COMPILE_FLAGS "-ObjC")
 > }}}

 BBEdit search failed me.

 > What do you mean by "fixing flags"? If you mean removing `-ObjC`, I
 expect that is what caused this error. `@class` is Objective-C syntax. The
 compiler needs to be told to compile in Objective-C mode, which is
 presumably what the `-ObjC` flag was accomplishing.

 Well, obviously a flag not supported by GCC must not be used with GCC. So
 flags are wrong.
 If GCC cannot compile the port, it should be blacklisted, or if only one
 module fails, it should be disabled, assuming a fix to the syntax is
 bothersome to come up with.

-- 
Ticket URL: <https://trac.macports.org/ticket/70087#comment:5>
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