diff --git a/js/src/jit-test/tests/basic/bug625399.js b/js/src/jit-test/tests/basic/bug625399.js
new file mode 100644
index 000000000000..e45cf21d8d83
--- /dev/null
+++ b/js/src/jit-test/tests/basic/bug625399.js
@@ -0,0 +1,7 @@
+function a(bb) {
+    "use strict";
+    return;
+    this.d = function() { bb; };
+}
+for (var i = 0; i <= RUNLOOP; i++)
+    a();
diff --git a/js/src/jstracer.cpp b/js/src/jstracer.cpp
index dfc985bff26e..7b196cffa774 100644
--- a/js/src/jstracer.cpp
+++ b/js/src/jstracer.cpp
@@ -16348,6 +16348,11 @@ TraceRecorder::record_JSOP_UNBRAND()
 JS_REQUIRES_STACK AbortableRecordingStatus
 TraceRecorder::record_JSOP_UNBRANDTHIS()
 {
+    /* In case of primitive this, do nothing. */
+    JSStackFrame *fp = cx->fp();
+    if (fp->fun()->inStrictMode() && !fp->thisValue().isObject())
+        return ARECORD_CONTINUE;
+
     LIns* this_ins;
     RecordingStatus status = getThis(this_ins);
     if (status != RECORD_CONTINUE)