diff --git a/hphp/runtime/base/thread_info.cpp b/hphp/runtime/base/thread_info.cpp
index 0bb940c1e..ff743313e 100644
--- a/hphp/runtime/base/thread_info.cpp
+++ b/hphp/runtime/base/thread_info.cpp
@@ -83,7 +83,6 @@ void ThreadInfo::GetExecutionSamples(std::map<Executing, int> &counts) {
 }
 
 void ThreadInfo::onSessionInit() {
-  m_top = nullptr;
   m_reqInjectionData.onSessionInit();
 
   // Take the address of the cached per-thread stackLimit, and use this to allow
diff --git a/hphp/runtime/base/types.h b/hphp/runtime/base/types.h
index 85143eb2f..57c8fd448 100644
--- a/hphp/runtime/base/types.h
+++ b/hphp/runtime/base/types.h
@@ -433,7 +433,6 @@ public:
 namespace VM {
 class GlobalNameValueTableWrapper;
 }
-class FrameInjection;
 class ObjectAllocatorBase;
 class Profiler;
 class CodeCoverage;
@@ -463,7 +462,6 @@ public:
   static DECLARE_THREAD_LOCAL_NO_CHECK(ThreadInfo, s_threadInfo);
 
   std::vector<ObjectAllocatorBase *> m_allocators;
-  FrameInjection *m_top;
   RequestInjectionData m_reqInjectionData;
 
   // For infinite recursion detection.  m_stacklimit is the lowest
diff --git a/hphp/runtime/eval/debugger/break_point.cpp b/hphp/runtime/eval/debugger/break_point.cpp
index 4614e69a0..1a6e71bdf 100644
--- a/hphp/runtime/eval/debugger/break_point.cpp
+++ b/hphp/runtime/eval/debugger/break_point.cpp
@@ -807,11 +807,6 @@ bool BreakPointInfo::checkStack(InterruptSite &site) {
   return true;
 }
 
-bool BreakPointInfo::checkFrame(FrameInjection *frame) {
-  const_assert(false);
-  return true;
-}
-
 bool BreakPointInfo::checkClause() {
   if (!m_clause.empty()) {
     if (m_php.empty()) {
diff --git a/hphp/runtime/eval/debugger/break_point.h b/hphp/runtime/eval/debugger/break_point.h
index f1e0bfc00..89065fe96 100644
--- a/hphp/runtime/eval/debugger/break_point.h
+++ b/hphp/runtime/eval/debugger/break_point.h
@@ -227,7 +227,6 @@ private:
   bool checkUrl(std::string &url);
   bool checkLines(int line);
   bool checkStack(InterruptSite &site);
-  bool checkFrame(FrameInjection *frame);
   bool checkClause();
 };
 
diff --git a/hphp/runtime/eval/debugger/cmd/cmd_flow_control.h b/hphp/runtime/eval/debugger/cmd/cmd_flow_control.h
index aa573ecb1..eee2f78e7 100644
--- a/hphp/runtime/eval/debugger/cmd/cmd_flow_control.h
+++ b/hphp/runtime/eval/debugger/cmd/cmd_flow_control.h
@@ -25,16 +25,11 @@ namespace HPHP { namespace Eval {
 DECLARE_BOOST_TYPES(CmdFlowControl);
 class CmdFlowControl : public DebuggerCommand {
 public:
-  CmdFlowControl(Type type)
-      : DebuggerCommand(type), m_count(1), m_frame(nullptr), m_nframe(nullptr),
-        m_stackDepth(0), m_vmDepth(0) { }
+  explicit CmdFlowControl(Type type)
+      : DebuggerCommand(type), m_count(1), m_stackDepth(0), m_vmDepth(0) { }
 
   int decCount() { assert(m_count > 0); return --m_count;}
   int getCount() const { assert(m_count > 0); return m_count;}
-  void setFrame(FrameInjection *frame) { m_frame = frame;}
-  FrameInjection *getFrame() const { return m_frame;}
-  void setNegativeFrame(FrameInjection *frame) { m_nframe = frame;}
-  FrameInjection *getNegativeFrame() const { return m_nframe;}
   void setFileLine(const std::string &loc) { m_loc = loc;}
   const std::string &getFileLine() const { return m_loc;}
 
@@ -51,8 +46,6 @@ public:
 
 private:
   int16_t m_count;
-  FrameInjection *m_frame;  // which frame to break next time
-  FrameInjection *m_nframe; // definitely not to break with this frame
   std::string m_loc; // last break's source location
   bool m_smallStep;
 
diff --git a/hphp/runtime/eval/debugger/cmd/cmd_interrupt.cpp b/hphp/runtime/eval/debugger/cmd/cmd_interrupt.cpp
index d73fd6f74..b9bb45607 100644
--- a/hphp/runtime/eval/debugger/cmd/cmd_interrupt.cpp
+++ b/hphp/runtime/eval/debugger/cmd/cmd_interrupt.cpp
@@ -310,10 +310,6 @@ bool CmdInterrupt::shouldBreak(const BreakPointInfoPtrVec &bps) {
   return false;
 }
 
-FrameInjection *CmdInterrupt::getFrame() {
-  return nullptr;
-}
-
 std::string CmdInterrupt::getFileLine() const {
   string ret;
   if (m_site) {
diff --git a/hphp/runtime/eval/debugger/cmd/cmd_interrupt.h b/hphp/runtime/eval/debugger/cmd/cmd_interrupt.h
index 17f349c99..ac326a7b0 100644
--- a/hphp/runtime/eval/debugger/cmd/cmd_interrupt.h
+++ b/hphp/runtime/eval/debugger/cmd/cmd_interrupt.h
@@ -52,7 +52,6 @@ public:
   virtual void recvImpl(DebuggerThriftBuffer &thrift);
 
   bool shouldBreak(const BreakPointInfoPtrVec &bps);
-  FrameInjection *getFrame();
   std::string getFileLine() const;
 
   InterruptSite *getSite() { return m_site;}
diff --git a/hphp/system/classes/exception.php b/hphp/system/classes/exception.php
index 528c6d5dd..e2d94255e 100644
--- a/hphp/system/classes/exception.php
+++ b/hphp/system/classes/exception.php
@@ -135,7 +135,6 @@ class Exception {
  * @return     mixed   Returns the Exception stack trace as a string.
  */
   final function getTraceAsString() {
-    // works with the new FrameInjection-based stacktrace.
     $i = 0;
     $s = "";
     foreach ($this->getTrace() as $frame) {