[PATCH 15/14] force SIGCHLD to the timer-thread

[Eric Wong <e@80x24.org>]

This is needed to prevent spurious wakeup on FreeBSD 11.1
to pass test/-ext-/gvl/test_last_thread.rb
---
 signal.c         | 1 +
 thread_pthread.c | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/signal.c b/signal.c
index 90d7824b2b..1f8e26340f 100644
--- a/signal.c
+++ b/signal.c
@@ -749,6 +749,7 @@ rb_enable_interrupt(void)
 #ifdef HAVE_PTHREAD_SIGMASK
     sigset_t mask;
     sigemptyset(&mask);
+    sigaddset(&mask, RUBY_SIGCHLD); /* timer-thread handles this */
     pthread_sigmask(SIG_SETMASK, &mask, NULL);
 #endif
 }
diff --git a/thread_pthread.c b/thread_pthread.c
index 4053a22eac..6ac7728ad9 100644
--- a/thread_pthread.c
+++ b/thread_pthread.c
@@ -1479,6 +1479,13 @@ static void *
 thread_timer(void *p)
 {
     rb_global_vm_lock_t *gvl = (rb_global_vm_lock_t *)p;
+#ifdef HAVE_PTHREAD_SIGMASK /* mainly to enable SIGCHLD */
+    {
+        sigset_t mask;
+        sigemptyset(&mask);
+        pthread_sigmask(SIG_SETMASK, &mask, NULL);
+    }
+#endif
 
     if (TT_DEBUG) WRITE_CONST(2, "start timer thread\n");
 
-- 
EW