Macro: ac_cxx_dynamic_cast

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

# ac_cxx_dynamic_cast

## Synopsis

`AC_CXX_DYNAMIC_CAST`

## Version

1.1.1.1 (2001/07/26) C++_Support @ ac-archive-0.5.32

## Author

Luc Maisonobe

## Description

If the compiler supports dynamic_cast<>, define HAVE_DYNAMIC_CAST.

## M4 Source Code

    AC_DEFUN([AC_CXX_DYNAMIC_CAST],
    [AC_CACHE_CHECK(whether the compiler supports dynamic_cast<>,
    ac_cv_cxx_dynamic_cast,
    [AC_LANG_SAVE
     AC_LANG_CPLUSPLUS
     AC_TRY_COMPILE([#include <typeinfo>
    class Base { public : Base () {} virtual void f () = 0;};
    class Derived : public Base { public : Derived () {} virtual void f () {} };],[
    Derived d; Base& b=d; return dynamic_cast<Derived*>(&b) ? 0 : 1;],
     ac_cv_cxx_dynamic_cast=yes, ac_cv_cxx_dynamic_cast=no)
     AC_LANG_RESTORE
    ])
    if test "$ac_cv_cxx_dynamic_cast" = yes; then
      AC_DEFINE(HAVE_DYNAMIC_CAST,,[define if the compiler supports dynamic_cast<>])
    fi
    ])