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| author | Enrico M. Crisostomo <enrico.m.crisostomo@gmail.com> | 2014-02-24 16:31:42 +0100 |
|---|---|---|
| committer | Peter Simons <simons@cryp.to> | 2014-02-24 16:32:42 +0100 |
| commit | fbcd388c05e92dea3d779d243fa2f93463b7abcf (patch) | |
| tree | 6d9af20e428523f064997b89e45eb003edc12c37 /m4/ax_cxx_have_hash.m4 | |
| parent | 3d1e2b6f21df708eb564d1714cd15a1a835d2016 (diff) | |
| download | autoconf-archive-fbcd388c05e92dea3d779d243fa2f93463b7abcf.tar.gz | |
AX_CXX_HAVE_HASH: initial version
Diffstat (limited to 'm4/ax_cxx_have_hash.m4')
| -rw-r--r-- | m4/ax_cxx_have_hash.m4 | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/m4/ax_cxx_have_hash.m4 b/m4/ax_cxx_have_hash.m4 new file mode 100644 index 0000000..ee5255b --- /dev/null +++ b/m4/ax_cxx_have_hash.m4 @@ -0,0 +1,54 @@ +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_cxx_have_hash.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CXX_HAVE_HASH() +# +# DESCRIPTION +# +# This macros checks if std::hash, added in C++11, is defined in the +# <functional> header. +# +# If it is, define the ax_cv_cxx_have_hash environment variable to "yes" +# and define HAVE_CXX_HASH. +# +# NOTE: This macros depends on AX_CXX_NAMESPACES. +# +# LICENSE +# +# Copyright (c) 2014 Enrico M. Crisostomo <enrico.m.crisostomo@gmail.com> +# +# 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 1 + +AC_DEFUN([AX_CXX_HAVE_HASH], + [AC_CACHE_CHECK( + [for std::hash in functional], + ax_cv_cxx_have_hash, + [AC_REQUIRE([AX_CXX_NAMESPACES]) + AC_LANG_PUSH([C++]) + AC_COMPILE_IFELSE([AC_LANG_PROGRAM( + [ + [#include <functional> + #include <string>] + [using std::hash;] + ], + [] + )], + [ax_cv_cxx_have_hash=yes], + [ax_cv_cxx_have_hash=no] + ) + AC_LANG_POP([C++])]) + if test x"$ax_cv_cxx_have_hash" = "xyes" + then + AC_DEFINE(HAVE_CXX_HASH, + 1, + [Define if functional defines the std::hash class.]) + fi + ]) |