diff --git a/lib/Support/Unix/Signals.inc b/lib/Support/Unix/Signals.inc
index e7696c2f7ee..26fd5c3f4e6 100644
--- a/lib/Support/Unix/Signals.inc
+++ b/lib/Support/Unix/Signals.inc
@@ -139,6 +139,11 @@ static void UnregisterHandlers() {
 /// NB: This must be an async signal safe function. It cannot allocate or free
 /// memory, even in debug builds.
 static void RemoveFilesToRemove() {
+  // Avoid constructing ManagedStatic in the signal handler.
+  // If FilesToRemove is not constructed, there are no files to remove.
+  if (!FilesToRemove.isConstructed())
+    return;
+
   // We avoid iterators in case of debug iterators that allocate or release
   // memory.
   std::vector<std::string>& FilesToRemoveRef = *FilesToRemove;
@@ -200,10 +205,12 @@ static RETSIGTYPE SignalHandler(int Sig) {
   }
 
   // Otherwise if it is a fault (like SEGV) run any handler.
-  std::vector<std::pair<void (*)(void *), void *>>& CallBacksToRunRef =
-      *CallBacksToRun;
-  for (unsigned i = 0, e = CallBacksToRun->size(); i != e; ++i)
-    CallBacksToRunRef[i].first(CallBacksToRunRef[i].second);
+  if (CallBacksToRun.isConstructed()) {
+    std::vector<std::pair<void (*)(void *), void *>>& CallBacksToRunRef =
+        *CallBacksToRun;
+    for (unsigned i = 0, e = CallBacksToRun->size(); i != e; ++i)
+      CallBacksToRunRef[i].first(CallBacksToRunRef[i].second);
+  }
 
 #ifdef __s390__
   // On S/390, certain signals are delivered with PSW Address pointing to