snix/m4/using_operator.m4
Vincent Ambo afe04691ac Squashed 'third_party/glog/' content from commit 9ef754a3023
git-subtree-dir: third_party/glog
git-subtree-split: 9ef754a3023e6fd10f20fe53dfca96dd898182e3
2020-05-27 01:26:30 +01:00

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624 B
Text

AC_DEFUN([AC_CXX_USING_OPERATOR],
[AC_CACHE_CHECK(
whether compiler supports using ::operator<<,
ac_cv_cxx_using_operator,
[AC_LANG_SAVE
AC_LANG_CPLUSPLUS
AC_TRY_COMPILE([#include <iostream>
std::ostream& operator<<(std::ostream&, struct s);],
[using ::operator<<; return 0;],
ac_cv_cxx_using_operator=1,
ac_cv_cxx_using_operator=0)
AC_LANG_RESTORE])
if test "$ac_cv_cxx_using_operator" = 1; then
AC_DEFINE(HAVE_USING_OPERATOR, 1, [define if the compiler supports using expression for operator])
fi])