[tsan] Add interceptor for xpc_connection_cancel to avoid false positives

TSan reports a false positive when using xpc_connection_cancel. We're missing a happens-before edge from xpc_connection_cancel to the event handler on the same connection.

Differential Revision: https://reviews.llvm.org/D31475



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@299086 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 0 deletions

diff --git a/test/tsan/Darwin/xpc-cancel.mm b/test/tsan/Darwin/xpc-cancel.mm
new file mode 100644
index 000000000..5e326b7e4
--- /dev/null
+++ b/test/tsan/Darwin/xpc-cancel.mm
@@ -0,0 +1,37 @@
+// RUN: %clang_tsan %s -o %t -framework Foundation
+// RUN: %run %t 2>&1 | FileCheck %s
+
+#import <Foundation/Foundation.h>
+#import <xpc/xpc.h>
+
+long global;
+
+int main(int argc, const char *argv[]) {
+  fprintf(stderr, "Hello world.\n");
+
+  dispatch_queue_t server_q = dispatch_queue_create("server.queue", DISPATCH_QUEUE_CONCURRENT);
+  xpc_connection_t server_conn = xpc_connection_create(NULL, server_q);
+
+  xpc_connection_set_event_handler(server_conn, ^(xpc_object_t client) {
+    if (client == XPC_ERROR_CONNECTION_INTERRUPTED || client == XPC_ERROR_CONNECTION_INVALID) {
+      global = 43;
+      
+      dispatch_async(dispatch_get_main_queue(), ^{
+        CFRunLoopStop(CFRunLoopGetCurrent());
+      });
+    }
+  });
+  xpc_connection_resume(server_conn);
+  
+  global = 42;
+  
+  xpc_connection_cancel(server_conn);
+  
+  CFRunLoopRun();
+
+  fprintf(stderr, "Done.\n");
+}
+
+// CHECK: Hello world.
+// CHECK-NOT: WARNING: ThreadSanitizer
+// CHECK: Done.