# Enable GNU extensions.
# Define this here, not in acconfig's @TOP@ section, since definitions
# in the latter don't make it into the configure-time tests.
-AC_GNU_SOURCE
+AC_USE_SYSTEM_EXTENSIONS
AC_DEFINE([__USE_BSD], 1, [Enable BSD extensions])
+AC_DEFINE([_POSIX_C_SOURCE], 200809L, [Enable POSIX features])
dnl Checks for programs.
AM_PROG_CC_C_O
dnl Checks for header files.
dnl We do this in multiple stages, because unlike Linux all the other operating systems really suck and don't include their own dependencies.
-AC_CHECK_HEADERS([syslog.h sys/file.h sys/param.h sys/resource.h sys/socket.h sys/time.h sys/un.h sys/wait.h netdb.h arpa/inet.h dirent.h curses.h ifaddrs.h])
+AC_CHECK_HEADERS([syslog.h sys/file.h sys/param.h sys/resource.h sys/socket.h sys/time.h sys/un.h sys/wait.h netdb.h arpa/inet.h dirent.h curses.h ifaddrs.h stdatomic.h])
dnl Checks for typedefs, structures, and compiler characteristics.
MeshLink_ATTRIBUTE(__malloc__)