--- a/js/src/vm/Stack.cpp
+++ b/js/src/vm/Stack.cpp
@@ -582,16 +582,17 @@ FrameIter::settleOnActivation()
     }
 }
 
 FrameIter::Data::Data(JSContext* cx, DebuggerEvalOption debuggerEvalOption,
                       JSPrincipals* principals)
   : cx_(cx),
     debuggerEvalOption_(debuggerEvalOption),
     principals_(principals),
+    state_(DONE),
     pc_(nullptr),
     interpFrames_(nullptr),
     activations_(cx->runtime()),
     jitFrames_(),
     ionInlineFrameNo_(0),
     wasmFrames_()
 {
 }