# ============================================================================== # http://www.gnu.org/software/autoconf-archive/ax_cxx_have_numeric_limits.html # ============================================================================== # # SYNOPSIS # # AX_CXX_HAVE_NUMERIC_LIMITS # # DESCRIPTION # # If the compiler has numeric_limits, define HAVE_NUMERIC_LIMITS. # # LICENSE # # Copyright (c) 2008 Todd Veldhuizen # Copyright (c) 2008 Luc Maisonobe # # Copying and distribution of this file, with or without modification, are # permitted in any medium without royalty provided the copyright notice # and this notice are preserved. This file is offered as-is, without any # warranty. #serial 6 AU_ALIAS([AC_CXX_HAVE_NUMERIC_LIMITS], [AX_CXX_HAVE_NUMERIC_LIMITS]) AC_DEFUN([AX_CXX_HAVE_NUMERIC_LIMITS], [AC_CACHE_CHECK(whether the compiler has numeric_limits, ax_cv_cxx_have_numeric_limits, [AC_REQUIRE([AX_CXX_NAMESPACES]) AC_LANG_SAVE AC_LANG_CPLUSPLUS AC_TRY_COMPILE([#include #ifdef HAVE_NAMESPACES using namespace std; #endif],[double e = numeric_limits::epsilon(); return 0;], ax_cv_cxx_have_numeric_limits=yes, ax_cv_cxx_have_numeric_limits=no) AC_LANG_RESTORE ]) if test "$ax_cv_cxx_have_numeric_limits" = yes; then AC_DEFINE(HAVE_NUMERIC_LIMITS,,[define if the compiler has numeric_limits]) fi ])