# no need for multithreaded mbrtowc (all programs are single threaded).
AC_DEFINE([GNULIB_MBRTOWC_SINGLE_THREAD], [1], [Define to 1.])
+# As the wcwidth replacement module is not used by the library, there is
+# no need to support varying locales (programs set locale once at startup).
+AC_DEFINE([GNULIB_WCHAR_SINGLE_LOCALE], [1], [Define to 1.])
+
AS_IF([test x"$gl_cv_lib_readline" = x"no"],
[AS_IF([test x"$with_readline" = x"yes"],
[AC_MSG_FAILURE([--with-readline requested but readline was not found])],