xref: /llvm-project/compiler-rt/test/tsan/libdispatch/dispatch_once_deadlock.c (revision 3879d3edef89879112080f57f0a9edf15d8d92a4)
1 // Check that dispatch_once() is always intercepted.
2 
3 // RUN: %clang_tsan %s -o %t
4 // RUN: not %env_tsan_opts=ignore_noninstrumented_modules=0 %run %t 2>&1 | FileCheck %s
5 
6 #include <dispatch/dispatch.h>
7 
8 #include <pthread.h>
9 #include <stdio.h>
10 
11 #include "../test.h"
12 
13 long g = 0;
14 long h = 0;
15 
16 __attribute__((disable_sanitizer_instrumentation))
f()17 void f() {
18   static dispatch_once_t onceToken;
19   dispatch_once(&onceToken, ^{
20     g++;
21   });
22   h++;
23 }
24 
25 // Required for dyld macOS 12.0+
26 #if (__APPLE__)
27 __attribute__((weak))
28 #endif
29 __attribute__((disable_sanitizer_instrumentation))
30 extern void
__tsan_on_report()31 __tsan_on_report() {
32   fprintf(stderr, "Report.\n");
33 
34   // Without these annotations this test deadlocks for COMPILER_RT_DEBUG=ON
35   // builds.  Conceptually, the TSan runtime does not support reentrancy from
36   // runtime callbacks, but the main goal here is just to check that
37   // dispatch_once() is always intercepted.
38   AnnotateIgnoreSyncBegin(__FILE__, __LINE__);
39   f();
40   AnnotateIgnoreSyncEnd(__FILE__, __LINE__);
41 }
42 
main()43 int main() {
44   fprintf(stderr, "Hello world.\n");
45 
46   f();
47 
48   pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
49   pthread_mutex_unlock(&mutex); // Unlock of an unlocked mutex
50 
51   fprintf(stderr, "g = %ld.\n", g);
52   fprintf(stderr, "h = %ld.\n", h);
53   fprintf(stderr, "Done.\n");
54 }
55 
56 // CHECK: Hello world.
57 // CHECK: Report.
58 // CHECK: g = 1
59 // CHECK: h = 2
60 // CHECK: Done.
61