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Diffstat (limited to 'm4/ac_cxx_have_numeric_limits.m4')
| -rw-r--r-- | m4/ac_cxx_have_numeric_limits.m4 | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/m4/ac_cxx_have_numeric_limits.m4 b/m4/ac_cxx_have_numeric_limits.m4 new file mode 100644 index 0000000..bb041e8 --- /dev/null +++ b/m4/ac_cxx_have_numeric_limits.m4 @@ -0,0 +1,38 @@ +# =========================================================================== +# http://autoconf-archive.cryp.to/ac_cxx_have_numeric_limits.html +# =========================================================================== +# +# SYNOPSIS +# +# AC_CXX_HAVE_NUMERIC_LIMITS +# +# DESCRIPTION +# +# If the compiler has numeric_limits<T>, define HAVE_NUMERIC_LIMITS. +# +# LICENSE +# +# Copyright (c) 2008 Todd Veldhuizen +# Copyright (c) 2008 Luc Maisonobe <luc@spaceroots.org> +# +# 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. + +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 +]) |