diff -r 0bda2308eded -r ad45b3802d4e src/hotspot/share/compiler/compileTask.cpp
--- a/src/hotspot/share/compiler/compileTask.cpp	Wed May 01 12:41:26 2019 -0400
+++ b/src/hotspot/share/compiler/compileTask.cpp	Wed May 01 12:31:29 2019 -0700
@@ -396,6 +396,7 @@
   ResourceMark rm(thread);
 
   if (!_is_success) {
+    assert(_failure_reason != NULL, "missing");
     const char* reason = _failure_reason != NULL ? _failure_reason : "unknown";
     log->elem("failure reason='%s'", reason);
   }