Index: lib/Support/Unix/Signals.inc
===================================================================
--- lib/Support/Unix/Signals.inc
+++ lib/Support/Unix/Signals.inc
@@ -334,6 +334,10 @@
       if (auto OldInterruptFunction = InterruptFunction.exchange(nullptr))
         return OldInterruptFunction();
 
+      // Send a special return code that drivers can check for.
+      if (Sig == SIGPIPE)
+        exit(71);
+
       raise(Sig);   // Execute the default handler.
       return;
    }