Macro: ac_cxx_enum_computations

Back to the Main Page. | # ac_cxx_enum_computations | Download the M4 Source.

Synopsis

  `AC_CXX_ENUM_COMPUTATIONS`

Version

  1.1.1.1 (2001/07/26) C++_Support @ ac-archive-0.5.39

Author

  Luc Maisonobe

Description

  If the compiler handle computations inside an enum, define HAVE_ENUM_COMPUTATIONS.

M4 Source Code

      AC_DEFUN([AC_CXX_ENUM_COMPUTATIONS],
      [AC_CACHE_CHECK(whether the compiler handle computations inside an enum,
      ac_cv_cxx_enum_computations,
      [AC_LANG_SAVE
       AC_LANG_CPLUSPLUS
       AC_TRY_COMPILE([
      struct A { enum { a = 5, b = 7, c = 2 }; };
      struct B { enum { a = 1, b = 6, c = 9 }; };
      template<class T1, class T2> struct Z
      { enum { a = (T1::a > T2::a) ? T1::a : T2::b,
               b = T1::b + T2::b,
               c = (T1::c * T2::c + T2::a + T1::a)
             };
      };],[
      return (((int)Z<A,B>::a == 5)
           && ((int)Z<A,B>::b == 13)
           && ((int)Z<A,B>::c == 24)) ? 0 : 1;],
       ac_cv_cxx_enum_computations=yes, ac_cv_cxx_enum_computations=no)
       AC_LANG_RESTORE
      ])
      if test "$ac_cv_cxx_enum_computations" = yes; then
        AC_DEFINE(HAVE_ENUM_COMPUTATIONS,,
                  [define if the compiler handle computations inside an enum])
      fi
      ])