[MacPorts] #62462: opencv4 upgrade fails

[MacPorts]

#62462: opencv4 upgrade fails
----------------------+----------------------
  Reporter:  dershow  |      Owner:  stromnov
      Type:  defect   |     Status:  assigned
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:
Resolution:           |   Keywords:
      Port:  opencv4  |
----------------------+----------------------

Comment (by mascguy):

 The compilation error on the 10.12 buildbot is as follows:

 {{{
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/imgcodecs/src/macosx_conversions.mm:6:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/imgcodecs/src/apple_conversions.h:8:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core.hpp:54:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/base.hpp:58:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd.hpp:81:
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd_wrapper.hpp:45:160:
 error: too many arguments provided to function-like macro invocation
     static CV_CONSTEXPR std::true_type check(typename
 std::is_same<typename
 std::decay<decltype(std::declval<T>().operator()(std::declval<Args>()...))>::type,
 Ret>::type*);
 ^
 /usr/include/AssertMacros.h:1291:10: note: macro 'check' defined here
         #define check(assertion)  __Check(assertion)
                 ^
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/imgcodecs/src/macosx_conversions.mm:6:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/imgcodecs/src/apple_conversions.h:8:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core.hpp:54:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/base.hpp:58:
 In file included from
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd.hpp:81:
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd_wrapper.hpp:45:40:
 warning: variable templates are a C++14 extension [-Wc++14-extensions]
     static CV_CONSTEXPR std::true_type check(typename
 std::is_same<typename
 std::decay<decltype(std::declval<T>().operator()(std::declval<Args>()...))>::type,
 Ret>::type*);
                                        ^
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd_wrapper.hpp:45:40:
 error: declaration of constexpr static data member 'check' requires an
 initializer
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvstd_wrapper.hpp:47:31:
 error: constexpr can only be used in variable and function declarations
     template<typename> static CV_CONSTEXPR std::false_type check(...);
                               ^
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/cvdef.h:757:26:
 note: expanded from macro 'CV_CONSTEXPR'
 #    define CV_CONSTEXPR constexpr
                          ^
 }}}

 With the following potential hint:

 {{{
 /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_graphics_opencv4/opencv4/work/opencv-4.5.1/modules/core/include/opencv2/core/utility.hpp:53:4:
 warning: Detected Apple 'check' macro definition, it can cause build
 conflicts. Please, include this header before any Apple headers.
 [-W#warnings]
 #  warning Detected Apple 'check' macro definition, it can cause build
 conflicts. Please, include this header before any Apple headers.
    ^
 }}}

 Not yet sure whether the errors are caused by header file include order
 (per the hint), the C++ standard declaration, Xcode Clang 9.0, or...

 Need to do more digging...

-- 
Ticket URL: <https://trac.macports.org/ticket/62462#comment:7>
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