llvmorg-11-init-4265-g2dcbdba8540.patch

diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
index 9a184c79798..733decfe52c 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
@@ -1021,7 +1021,7 @@ TSAN_INTERCEPTOR(int, pthread_create,
 
 TSAN_INTERCEPTOR(int, pthread_join, void *th, void **ret) {
   SCOPED_INTERCEPTOR_RAW(pthread_join, th, ret);
-  int tid = ThreadTid(thr, pc, (uptr)th);
+  int tid = ThreadConsumeTid(thr, pc, (uptr)th);
   ThreadIgnoreBegin(thr, pc);
   int res = BLOCK_REAL(pthread_join)(th, ret);
   ThreadIgnoreEnd(thr, pc);
@@ -1034,8 +1034,8 @@ TSAN_INTERCEPTOR(int, pthread_join, void *th, void **ret) {
 DEFINE_REAL_PTHREAD_FUNCTIONS
 
 TSAN_INTERCEPTOR(int, pthread_detach, void *th) {
-  SCOPED_TSAN_INTERCEPTOR(pthread_detach, th);
-  int tid = ThreadTid(thr, pc, (uptr)th);
+  SCOPED_INTERCEPTOR_RAW(pthread_detach, th);
+  int tid = ThreadConsumeTid(thr, pc, (uptr)th);
   int res = REAL(pthread_detach)(th);
   if (res == 0) {
     ThreadDetach(thr, pc, tid);
@@ -1055,8 +1055,8 @@ TSAN_INTERCEPTOR(void, pthread_exit, void *retval) {
 
 #if SANITIZER_LINUX
 TSAN_INTERCEPTOR(int, pthread_tryjoin_np, void *th, void **ret) {
-  SCOPED_TSAN_INTERCEPTOR(pthread_tryjoin_np, th, ret);
-  int tid = ThreadTid(thr, pc, (uptr)th);
+  SCOPED_INTERCEPTOR_RAW(pthread_tryjoin_np, th, ret);
+  int tid = ThreadConsumeTid(thr, pc, (uptr)th);
   ThreadIgnoreBegin(thr, pc);
   int res = REAL(pthread_tryjoin_np)(th, ret);
   ThreadIgnoreEnd(thr, pc);
@@ -1069,8 +1069,8 @@ TSAN_INTERCEPTOR(int, pthread_tryjoin_np, void *th, void **ret) {
 
 TSAN_INTERCEPTOR(int, pthread_timedjoin_np, void *th, void **ret,
                  const struct timespec *abstime) {
-  SCOPED_TSAN_INTERCEPTOR(pthread_timedjoin_np, th, ret, abstime);
-  int tid = ThreadTid(thr, pc, (uptr)th);
+  SCOPED_INTERCEPTOR_RAW(pthread_timedjoin_np, th, ret, abstime);
+  int tid = ThreadConsumeTid(thr, pc, (uptr)th);
   ThreadIgnoreBegin(thr, pc);
   int res = BLOCK_REAL(pthread_timedjoin_np)(th, ret, abstime);
   ThreadIgnoreEnd(thr, pc);
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl.h b/compiler-rt/lib/tsan/rtl/tsan_rtl.h
index 3a8231bda9a..30e144fbd00 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl.h
@@ -772,7 +772,7 @@ int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached);
 void ThreadStart(ThreadState *thr, int tid, tid_t os_id,
                  ThreadType thread_type);
 void ThreadFinish(ThreadState *thr);
-int ThreadTid(ThreadState *thr, uptr pc, uptr uid);
+int ThreadConsumeTid(ThreadState *thr, uptr pc, uptr uid);
 void ThreadJoin(ThreadState *thr, uptr pc, int tid);
 void ThreadDetach(ThreadState *thr, uptr pc, int tid);
 void ThreadFinalize(ThreadState *thr);
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cc b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cc
index fd95cfed4f5..13e457bd770 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cc
@@ -285,19 +285,34 @@ void ThreadFinish(ThreadState *thr) {
   ctx->thread_registry->FinishThread(thr->tid);
 }
 
-static bool FindThreadByUid(ThreadContextBase *tctx, void *arg) {
-  uptr uid = (uptr)arg;
-  if (tctx->user_id == uid && tctx->status != ThreadStatusInvalid) {
+struct ConsumeThreadContext {
+  uptr uid;
+  ThreadContextBase* tctx;
+};
+
+static bool ConsumeThreadByUid(ThreadContextBase *tctx, void *arg) {
+  ConsumeThreadContext *findCtx = (ConsumeThreadContext*)arg;
+  if (tctx->user_id == findCtx->uid && tctx->status != ThreadStatusInvalid) {
+    if (findCtx->tctx) {
+      // Ensure that user_id is unique. If it's not the case we are screwed.
+      // Something went wrong before, but now there is no way to recover.
+      // Returning a wrong thread is not an option, it may lead to very hard
+      // to debug false positives (e.g. if we join a wrong thread).
+      Report("ThreadSanitizer: dup thread with used id 0x%zx\n", findCtx->uid);
+      Die();
+    }
+    findCtx->tctx = tctx;
     tctx->user_id = 0;
-    return true;
   }
   return false;
 }
 
-int ThreadTid(ThreadState *thr, uptr pc, uptr uid) {
-  int res = ctx->thread_registry->FindThread(FindThreadByUid, (void*)uid);
-  DPrintf("#%d: ThreadTid uid=%zu tid=%d\n", thr->tid, uid, res);
-  return res;
+int ThreadConsumeTid(ThreadState *thr, uptr pc, uptr uid) {
+  ConsumeThreadContext findCtx = {uid, nullptr};
+  ctx->thread_registry->FindThread(ConsumeThreadByUid, &findCtx);
+  int tid = findCtx.tctx ? findCtx.tctx->tid : ThreadRegistry::kUnknownTid;
+  DPrintf("#%d: ThreadTid uid=%zu tid=%d\n", thr->tid, uid, tid);
+  return tid;
 }
 
 void ThreadJoin(ThreadState *thr, uptr pc, int tid) {