Macro: ac_cxx_have_numeric_limits

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Synopsis

  `AC_CXX_HAVE_NUMERIC_LIMITS`

Version

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

Author

  Luc Maisonobe

Description

  If the compiler has numeric_limits<T>, define HAVE_NUMERIC_LIMITS.

M4 Source Code

      AC_DEFUN([AC_CXX_HAVE_NUMERIC_LIMITS],
      [AC_CACHE_CHECK(whether the compiler has numeric_limits<T>,
      ac_cv_cxx_have_numeric_limits,
      [AC_REQUIRE([AC_CXX_NAMESPACES])
       AC_LANG_SAVE
       AC_LANG_CPLUSPLUS
       AC_TRY_COMPILE([#include <limits>
      #ifdef HAVE_NAMESPACES
      using namespace std;
      #endif],[double e = numeric_limits<double>::epsilon(); return 0;],
       ac_cv_cxx_have_numeric_limits=yes, ac_cv_cxx_have_numeric_limits=no)
       AC_LANG_RESTORE
      ])
      if test "$ac_cv_cxx_have_numeric_limits" = yes; then
        AC_DEFINE(HAVE_NUMERIC_LIMITS,,[define if the compiler has numeric_limits<T>])
      fi
      ])