Index: compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
===================================================================
--- compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -3506,7 +3506,7 @@
 INTERCEPTOR(uptr, ptrace, int request, int pid, void *addr, void *data) {
   void *ctx;
   COMMON_INTERCEPTOR_ENTER(ctx, ptrace, request, pid, addr, data);
-  __sanitizer_iovec local_iovec;
+  __sanitizer_iovec local_iovec = {};
 
   if (data) {
     if (request == ptrace_setregs) {
Index: compiler-rt/lib/sanitizer_common/sanitizer_posix.cpp
===================================================================
--- compiler-rt/lib/sanitizer_common/sanitizer_posix.cpp
+++ compiler-rt/lib/sanitizer_common/sanitizer_posix.cpp
@@ -156,7 +156,7 @@
 fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *errno_p) {
   if (ShouldMockFailureToOpen(filename))
     return kInvalidFd;
-  int flags;
+  int flags = 0;
   switch (mode) {
     case RdOnly: flags = O_RDONLY; break;
     case WrOnly: flags = O_WRONLY | O_CREAT | O_TRUNC; break;
Index: compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
===================================================================
--- compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
+++ compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
@@ -187,7 +187,7 @@
   }
 
   uptr operator*() {
-    sptr diff;
+    sptr diff = 0;
     begin = DecodeSLEB128(begin, end, &diff);
     previous += diff;
     return previous;
Index: compiler-rt/lib/tsan/rtl/tsan_dense_alloc.h
===================================================================
--- compiler-rt/lib/tsan/rtl/tsan_dense_alloc.h
+++ compiler-rt/lib/tsan/rtl/tsan_dense_alloc.h
@@ -162,7 +162,7 @@
     u64 cmp = atomic_load(&freelist_, memory_order_acquire);
     do {
       head->next = static_cast<IndexT>(cmp);
-      xchg = head_idx | (cmp & kCounterMask) + kCounterInc;
+      xchg = (head_idx | (cmp & kCounterMask)) + kCounterInc;
     } while (!atomic_compare_exchange_weak(&freelist_, &cmp, xchg,
                                            memory_order_acq_rel));
   }
Index: compiler-rt/lib/tsan/rtl/tsan_rtl.h
===================================================================
--- compiler-rt/lib/tsan/rtl/tsan_rtl.h
+++ compiler-rt/lib/tsan/rtl/tsan_rtl.h
@@ -730,7 +730,7 @@
 
 template <typename EventT>
 void TraceEvent(ThreadState *thr, EventT ev) {
-  EventT *evp;
+  EventT *evp = nullptr;
   if (!TraceAcquire(thr, &evp)) {
     TraceSwitchPart(thr);
     UNUSED bool res = TraceAcquire(thr, &evp);
Index: compiler-rt/lib/ubsan/ubsan_handlers_cxx.cpp
===================================================================
--- compiler-rt/lib/ubsan/ubsan_handlers_cxx.cpp
+++ compiler-rt/lib/ubsan/ubsan_handlers_cxx.cpp
@@ -127,6 +127,7 @@
     break;
   case CFITCK_ICall:
   case CFITCK_NVMFCall:
+  default:
     Die();
   }