diff --git a/compiler-rt/lib/tsan/rtl/tsan_report.cpp b/compiler-rt/lib/tsan/rtl/tsan_report.cpp
index a926c3761ccf91..001ba30b20ac94 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_report.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_report.cpp
@@ -126,7 +126,7 @@ static void PrintMutexSet(Vector<ReportMopMutex> const& mset) {
     if (i == 0)
       Printf(" (mutexes:");
     const ReportMopMutex m = mset[i];
-    Printf(" %s M%llu", m.write ? "write" : "read", m.id);
+    Printf(" %s M%u", m.write ? "write" : "read", m.id);
     Printf(i == mset.Size() - 1 ? ")" : ",");
   }
 }
@@ -211,13 +211,13 @@ static void PrintLocation(const ReportLocation *loc) {
 
 static void PrintMutexShort(const ReportMutex *rm, const char *after) {
   Decorator d;
-  Printf("%sM%lld%s%s", d.Mutex(), rm->id, d.Default(), after);
+  Printf("%sM%d%s%s", d.Mutex(), rm->id, d.Default(), after);
 }
 
 static void PrintMutexShortWithAddress(const ReportMutex *rm,
                                        const char *after) {
   Decorator d;
-  Printf("%sM%lld (%p)%s%s", d.Mutex(), rm->id,
+  Printf("%sM%d (%p)%s%s", d.Mutex(), rm->id,
          reinterpret_cast<void *>(rm->addr), d.Default(), after);
 }
 
@@ -225,11 +225,11 @@ static void PrintMutex(const ReportMutex *rm) {
   Decorator d;
   if (rm->destroyed) {
     Printf("%s", d.Mutex());
-    Printf("  Mutex M%llu is already destroyed.\n\n", rm->id);
+    Printf("  Mutex M%u is already destroyed.\n\n", rm->id);
     Printf("%s", d.Default());
   } else {
     Printf("%s", d.Mutex());
-    Printf("  Mutex M%llu (%p) created at:\n", rm->id,
+    Printf("  Mutex M%u (%p) created at:\n", rm->id,
            reinterpret_cast<void *>(rm->addr));
     Printf("%s", d.Default());
     PrintStack(rm->stack);
@@ -460,12 +460,12 @@ void PrintReport(const ReportDesc *rep) {
   } else if (rep->typ == ReportTypeDeadlock) {
     Printf("WARNING: DEADLOCK\n");
     for (uptr i = 0; i < rep->mutexes.Size(); i++) {
-      Printf("Goroutine %d lock mutex %llu while holding mutex %llu:\n", 999,
+      Printf("Goroutine %d lock mutex %u while holding mutex %u:\n", 999,
              rep->mutexes[i]->id,
              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
       PrintStack(rep->stacks[2*i]);
       Printf("\n");
-      Printf("Mutex %llu was previously locked here:\n",
+      Printf("Mutex %u was previously locked here:\n",
              rep->mutexes[(i + 1) % rep->mutexes.Size()]->id);
       PrintStack(rep->stacks[2*i + 1]);
       Printf("\n");
diff --git a/compiler-rt/lib/tsan/rtl/tsan_report.h b/compiler-rt/lib/tsan/rtl/tsan_report.h
index d68c2db88828f1..da4f148d89ef4d 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_report.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_report.h
@@ -43,7 +43,7 @@ struct ReportStack {
 };
 
 struct ReportMopMutex {
-  u64 id;
+  int id;
   bool write;
 };
 
@@ -91,7 +91,7 @@ struct ReportThread {
 };
 
 struct ReportMutex {
-  u64 id;
+  int id;
   uptr addr;
   bool destroyed;
   ReportStack *stack;
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl_report.cpp b/compiler-rt/lib/tsan/rtl/tsan_rtl_report.cpp
index 69a56a38efbb68..1fd16d09c553d6 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl_report.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl_report.cpp
@@ -193,7 +193,7 @@ void ScopedReportBase::AddMemoryAccess(uptr addr, uptr external_tag, Shadow s,
     mop->stack->suppressable = true;
   for (uptr i = 0; i < mset->Size(); i++) {
     MutexSet::Desc d = mset->Get(i);
-    u64 id = this->AddMutex(d.addr, d.stack_id);
+    int id = this->AddMutex(d.addr, d.stack_id);
     ReportMopMutex mtx = {id, d.write};
     mop->mset.PushBack(mtx);
   }