1 files changed, 55 insertions, 0 deletions
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan11.go b/libgo/misc/cgo/testsanitizers/src/tsan11.go
new file mode 100644
index 00000000000..70ac9c8ae2c
--- /dev/null
+++ b/libgo/misc/cgo/testsanitizers/src/tsan11.go
@@ -0,0 +1,55 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// This program hung when run under the C/C++ ThreadSanitizer. TSAN defers
+// asynchronous signals until the signaled thread calls into libc. The runtime's
+// sysmon goroutine idles itself using direct usleep syscalls, so it could
+// run for an arbitrarily long time without triggering the libc interceptors.
+// See https://golang.org/issue/18717.
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+/*
+#cgo CFLAGS: -g -fsanitize=thread
+#cgo LDFLAGS: -g -fsanitize=thread
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void raise_usr2(int signo) {
+	raise(SIGUSR2);
+}
+
+static void register_handler(int signo) {
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(sa));
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_ONSTACK;
+	sa.sa_handler = raise_usr2;
+
+	if (sigaction(SIGUSR1, &sa, NULL) != 0) {
+		perror("failed to register SIGUSR1 handler");
+		exit(EXIT_FAILURE);
+	}
+}
+*/
+import "C"
+
+func main() {
+	ch := make(chan os.Signal)
+	signal.Notify(ch, syscall.SIGUSR2)
+
+	C.register_handler(C.int(syscall.SIGUSR1))
+	syscall.Kill(syscall.Getpid(), syscall.SIGUSR1)
+
+	<-ch
+}