Hi, I'd like to check the presence of experimental/unordered_map and experimental/unordered_set so I have in configure.ac: AC_ARG_ENABLE([experimental], [ --enable-experimental enable unordered map and unordered set], AC_CXX_HEADER_UNORDERED_SET AC_CXX_HEADER_UNORDERED_MAP , AC_CXX_GNUCXX_HASHMAP AC_CXX_GNUCXX_HASHSET AS_IF([test x"$ax_cv_cxx_gnucxx_hashset" = xyes -a x"$ax_cv_cxx_gnucxx_hashmap" = xyes],[],AC_MSG_FAILURE([hash headers not found])) ) unordered_headers="unordered map and unordered set not found => using hash_map and hash_set headers" AS_IF([test x"$enable_experimental" = xyes], if test x"$ax_cv_cxx_unordered_map" = xyes -o x"$ax_cv_cxx_unordered_set" = xyes;then [unordered_headers=yes];else AC_MSG_WARN([$unordered_headers]);fi,unordered_headers="No. It will be used hash headers") #End of snippet. I've tested deleting /usr/include/c++/10/experimental/unordered_set and /usr/include/c++/10/experimental/unordered_map but it results in unordered_headers="yes" anyway. I'm using ax_cxx_header_unordered_map.m4 and ax_cxx_header_unordered_set.m4 macros. This is my system info: OS: Fedora 32: autoconf-archive-2019.01.06-5.fc32.noarch gcc-10.1.1-1.fc32.x86_64 gcc-c++-10.1.1-1.fc32.x86_64 autoconf-2.69-33.fc32.noarch libstdc++-devel-10.1.1-1.fc32.x86_64 Please could you help me? Am I doing something wrong? Thanks in advance! -- -- Sergio Belkin LPIC-2 Certified - http://www.lpi.org
