diff --git a/Zend/zend_signal.c b/Zend/zend_signal.c
index 8fe8ebc515c..6105fb11193 100644
--- a/Zend/zend_signal.c
+++ b/Zend/zend_signal.c
@@ -131,7 +131,7 @@ void zend_signal_handler_defer(int signo, siginfo_t *siginfo, void *context)
 
 /* {{{ zend_signal_handler_unblock
  * Handle deferred signal from HANDLE_UNBLOCK_ALARMS */
-void zend_signal_handler_unblock(TSRMLS_D)
+ZEND_API void zend_signal_handler_unblock(TSRMLS_D)
 {
 	zend_signal_queue_t *queue;
 	zend_signal_t zend_signal;
diff --git a/Zend/zend_signal.h b/Zend/zend_signal.h
index bc101320911..54f47ee54f9 100644
--- a/Zend/zend_signal.h
+++ b/Zend/zend_signal.h
@@ -79,7 +79,7 @@ extern ZEND_API zend_signal_globals_t zend_signal_globals;
 # define SIGNAL_END_CRITICAL()		zend_sigprocmask(SIG_SETMASK, &oldmask, NULL);
 
 void zend_signal_handler_defer(int signo, siginfo_t *siginfo, void *context);
-void zend_signal_handler_unblock();
+ZEND_API void zend_signal_handler_unblock();
 void zend_signal_activate(TSRMLS_D);
 void zend_signal_deactivate(TSRMLS_D);
 void zend_signal_startup();