Macro: ac_cxx_template_qualified_base_class

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# ac_cxx_template_qualified_base_class

Synopsis

  `AC_CXX_TEMPLATE_QUALIFIED_BASE_CLASS`

Version

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

Author

  Luc Maisonobe

Description

  If the compiler supports template-qualified base class specifiers, define HAVE_TEMPLATE_QUALIFIED_BASE_CLASS.

M4 Source Code

      AC_DEFUN([AC_CXX_TEMPLATE_QUALIFIED_BASE_CLASS],
      [AC_CACHE_CHECK(whether the compiler supports template-qualified base class specifiers,
      ac_cv_cxx_template_qualified_base_class,
      [AC_REQUIRE([AC_CXX_TYPENAME])
       AC_LANG_SAVE
       AC_LANG_CPLUSPLUS
       AC_TRY_COMPILE([
      #ifndef HAVE_TYPENAME
       #define typename
      #endif
      class Base1 { public : int f () const { return 1; } };
      class Base2 { public : int f () const { return 0; } };
      template<class X> struct base_trait        { typedef Base1 base; };
                        struct base_trait<float> { typedef Base2 base; };
      template<class T> class Weird : public base_trait<T>::base
      { public :
        typedef typename base_trait<T>::base base;
        int g () const { return f (); }
      };],[ Weird<float> z; return z.g ();],
       ac_cv_cxx_template_qualified_base_class=yes, ac_cv_cxx_template_qualified_base_class=no)
       AC_LANG_RESTORE
      ])
      if test "$ac_cv_cxx_template_qualified_base_class" = yes; then
        AC_DEFINE(HAVE_TEMPLATE_QUALIFIED_BASE_CLASS,,
                  [define if the compiler supports template-qualified base class specifiers])
      fi
      ])