-PKG_CHECK_MODULES(PTHREADSTUBS, pthread-stubs)
-AC_SUBST(PTHREADSTUBS_CFLAGS)
-AC_SUBST(PTHREADSTUBS_LIBS)
+dnl pthread-stubs is mandatory on targets where it exists
+case "$host_os" in
+cygwin* )
+ pthread_stubs_possible="no"
+ ;;
+* )
+ pthread_stubs_possible="yes"
+ ;;
+esac
+
+if test "x$pthread_stubs_possible" = xyes; then
+ PKG_CHECK_MODULES(PTHREADSTUBS, pthread-stubs)
+ AC_SUBST(PTHREADSTUBS_CFLAGS)
+ AC_SUBST(PTHREADSTUBS_LIBS)
+fi