[MacPorts] #64559: ncplot @4.9.12: Use the right flags and compiler

[MacPorts]

#64559: ncplot @4.9.12: Use the right flags and compiler
------------------------+----------------------
 Reporter:  ryandesign  |      Owner:  mf2k
     Type:  defect      |     Status:  assigned
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:  2.7.1
 Keywords:              |       Port:  ncplot
------------------------+----------------------
 The ncplot build is not using the cflags, cppflags, ldflags MacPorts wants
 it to. For example:

 https://build.macports.org/builders/ports-
 11_arm64-builder/builds/45812/steps/install-port/logs/stdio

 {{{
 /usr/bin/clang++ -arch arm64 -Wall -g -O2 -I/opt/X11/include -DPNG -Wno-
 write-strings -Wno-overflow -c ncplot.c
 clang: warning: treating 'c' input as 'c++' when in C++ mode, this
 behavior is deprecated [-Wdeprecated]
 }}}

 * `-Os` is not present but `-O2` is
 * `-I/opt/local/include` is not present but `-I/opt/X11/include` (which we
 don't want) is
 * `-stdlib=libc++` is not present which we would want when compiling C++
 software but in fact this port is erroneously using the C++ compiler to
 compile C code. That's coming from the portfile:

 {{{
 CC="${configure.cxx} [get_canonical_archflags cxx]"
 }}}

 The portfile could be simplified, and many of these problems could be
 corrected, by letting the makefile portgroup handle these details for you
 (though you'll probably still need to manually address the unwanted
 `-I/opt/X11/include` and `-L/opt/X11/lib` flags).

-- 
Ticket URL: <https://trac.macports.org/ticket/64559>
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