+ gl_PREREQ_SYS_H_WINSOCK2
+
+ dnl Check for declarations of anything we want to poison if the
+ dnl corresponding gnulib module is not in use.
+ gl_WARN_ON_USE_PREPARE([[
+/* Some systems require prerequisite headers. */
+#include <sys/types.h>
+#if !(defined __GLIBC__ && !defined __UCLIBC__) && HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#include <sys/select.h>
+ ]], [pselect select])