replaced null with uninit_null()

hphp/compiler/expression/scalar_expression.cpp

@@ -452,7 +452,7 @@ Variant ScalarExpression::getVariant() const {
     default:
       assert(false);
   }
-  return null;
+  return uninit_null();
 }
 
 bool ScalarExpression::getString(const std::string *&s) const {

hphp/idl/base.php

@@ -945,7 +945,7 @@ function php_escape_val($val) {
   } else if ($val === false) {
     return 'false';
   } else if ($val === null) {
-    return 'null';
+    return 'uninit_null()';
   } else {
     return var_export($val, true);
   }

hphp/runtime/base/array/array_data.cpp

@@ -234,7 +234,7 @@ ArrayData *ArrayData::pop(Variant &value) {
     value = getValue(pos);
     return remove(getKey(pos), getCount() > 1);
   }
-  value = null;
+  value = uninit_null();
   return nullptr;
 }
 
@@ -253,7 +253,7 @@ ArrayData *ArrayData::dequeue(Variant &value) {
 
     return ret;
   }
-  value = null;
+  value = uninit_null();
   return nullptr;
 }
 
@@ -372,7 +372,7 @@ Variant ArrayData::key() const {
   if (m_pos >= 0 && m_pos < size()) {
     return getKey(m_pos);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant ArrayData::value(ssize_t &pos) const {

hphp/runtime/base/array/array_util.cpp

@@ -70,7 +70,7 @@ Variant ArrayUtil::Chunk(CArrRef input, int size,
                          bool preserve_keys /* = false */) {
   if (size < 1) {
     throw_invalid_argument("size: %d", size);
-    return null;
+    return uninit_null();
   }
 
   Array ret = Array::Create();
@@ -562,7 +562,7 @@ Variant ArrayUtil::RandomKeys(CArrRef input, int num_req /* = 1 */) {
   if (num_req <= 0 || num_req > count) {
     raise_warning("Second argument has to be between 1 and the "
                   "number of elements in the array");
-    return null;
+    return uninit_null();
   }
 
   std::vector<ssize_t> indices;
@@ -588,7 +588,7 @@ Variant ArrayUtil::RandomKeys(CArrRef input, int num_req /* = 1 */) {
 Variant ArrayUtil::RandomValues(CArrRef input, int num_req /* = 1 */) {
   int count = input.size();
   if (num_req <= 0 || num_req > count) {
-    return null;
+    return uninit_null();
   }
 
   std::vector<ssize_t> indices;
@@ -772,7 +772,7 @@ Variant ArrayUtil::Map(CArrRef inputs, PFUNC_MAP map_function,
         if (k < arr.size()) {
           params.append(arr->getValueRef(positions[i][k]));
         } else {
-          params.append(null);
+          params.append(uninit_null());
         }
       }
 

hphp/runtime/base/array/hphp_array.cpp

@@ -390,7 +390,7 @@ Variant HphpArray::key() const {
     }
     return e->ikey;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant HphpArray::value(ssize_t& pos) const {
@@ -1407,7 +1407,7 @@ TypedValue* HphpArray::nvGet(const StringData* k) const {
 ArrayData* HphpArray::nvNew(TypedValue*& ret, bool copy) {
   HphpArray *a = this, *t = 0;
   if (copy) a = t = copyImpl();
-  if (UNLIKELY(!a->nextInsert(null))) {
+  if (UNLIKELY(!a->nextInsert(uninit_null()))) {
     ret = nullptr;
     return t;
   }
@@ -1620,7 +1620,7 @@ ArrayData* HphpArray::pop(Variant& value) {
         : a->findForInsert(e->ikey);
     a->erase(ei, true);
   } else {
-    value = null;
+    value = uninit_null();
   }
   // To match PHP-like semantics, the pop operation resets the array's
   // internal iterator.
@@ -1647,7 +1647,7 @@ ArrayData* HphpArray::dequeue(Variant& value) {
              a->findForInsert(e->ikey));
     a->compact(true);
   } else {
-    value = null;
+    value = uninit_null();
   }
   // To match PHP-like semantics, the dequeue operation resets the array's
   // internal iterator

hphp/runtime/base/builtin_functions.cpp

@@ -366,7 +366,7 @@ Variant vm_call_user_func(CVarRef function, CArrRef params,
   const HPHP::VM::Func* f = vm_decode_function(function, cf(), forwarding,
                                                obj, cls, invName);
   if (f == nullptr) {
-    return null;
+    return uninit_null();
   }
   Variant ret;
   g_vmContext->invokeFunc((TypedValue*)&ret, f, params, obj, cls,
@@ -401,12 +401,12 @@ Variant invoke_static_method(CStrRef s, CStrRef method, CArrRef params,
   HPHP::VM::Class* class_ = VM::Unit::lookupClass(s.get());
   if (class_ == nullptr) {
     o_invoke_failed(s.data(), method.data(), fatal);
-    return null;
+    return uninit_null();
   }
   const HPHP::VM::Func* f = class_->lookupMethod(method.get());
   if (f == nullptr || !(f->attrs() & HPHP::VM::AttrStatic)) {
     o_invoke_failed(s.data(), method.data(), fatal);
-    return null;
+    return uninit_null();
   }
   Variant ret;
   g_vmContext->invokeFunc((TypedValue*)&ret, f, params, nullptr, class_);
@@ -572,7 +572,7 @@ Variant throw_missing_arguments(const char *fn, int num, int level /* = 0 */) {
   } else {
     raise_warning("Missing argument %d for %s()", num, fn);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant throw_toomany_arguments(const char *fn, int num, int level /* = 0 */) {
@@ -581,7 +581,7 @@ Variant throw_toomany_arguments(const char *fn, int num, int level /* = 0 */) {
   } else if (level == 1 || RuntimeOption::WarnTooManyArguments) {
     raise_warning("Too many arguments for %s(), expected %d", fn, num);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant throw_wrong_arguments(const char *fn, int count, int cmin, int cmax,
@@ -593,7 +593,7 @@ Variant throw_wrong_arguments(const char *fn, int count, int cmin, int cmax,
     return throw_toomany_arguments(fn, cmax, level);
   }
   assert(false);
-  return null;
+  return uninit_null();
 }
 
 void throw_missing_arguments_nr(const char *fn, int num, int level /* = 0 */) {
@@ -634,7 +634,7 @@ Variant throw_missing_typed_argument(const char *fn,
     raise_error("Argument %d passed to %s() must be "
                 "an instance of %s, none given", arg, fn, type);
   }
-  return null;
+  return uninit_null();
 }
 
 void throw_bad_type_exception(const char *fmt, ...) {
@@ -676,7 +676,7 @@ void throw_invalid_argument(const char *fmt, ...) {
 
 Variant throw_fatal_unset_static_property(const char *s, const char *prop) {
   raise_error("Attempt to unset static property %s::$%s", s, prop);
-  return null;
+  return uninit_null();
 }
 
 void check_request_timeout_info(ThreadInfo *info, int lc) {

hphp/runtime/base/builtin_functions.h

@@ -285,14 +285,14 @@ bool isset(CArrRef v, CVarRef offset);
 bool isset(CArrRef v, litstr  offset, bool isString = false);
 bool isset(CArrRef v, CStrRef offset, bool isString = false);
 
-inline Variant unset(Variant &v)               { v.unset();   return null;}
-inline Variant unset(CVarRef v)                {              return null;}
-inline Variant setNull(Variant &v)             { v.setNull(); return null;}
+inline Variant unset(Variant &v)               { v.unset();   return uninit_null();}
+inline Variant unset(CVarRef v)                {              return uninit_null();}
+inline Variant setNull(Variant &v)             { v.setNull(); return uninit_null();}
 inline Object setNull(Object &v)               { v.reset();   return Object();}
 inline Array setNull(Array &v)                 { v.reset();   return Array();}
 inline String setNull(String &v)               { v.reset();   return String();}
-inline Variant unset(Object &v)                { v.reset();   return null;}
-inline Variant unset(Array &v)                 { v.reset();   return null;}
+inline Variant unset(Object &v)                { v.reset();   return uninit_null();}
+inline Variant unset(Array &v)                 { v.reset();   return uninit_null();}
 ///////////////////////////////////////////////////////////////////////////////
 // special variable contexts
 

hphp/runtime/base/class_info.h

@@ -336,7 +336,7 @@ public:
         return *(Object*)addr;
       default:
         assert(false);
-        return null;
+        return uninit_null();
     }
   }
 

hphp/runtime/base/execution_context.h

@@ -252,7 +252,7 @@ public:
   /**
    * Output buffering.
    */
-  void obStart(CVarRef handler = null);
+  void obStart(CVarRef handler = uninit_null());
   String obCopyContents();
   String obDetachContents();
   int obGetContentLength();

hphp/runtime/base/file/file.h

@@ -52,7 +52,7 @@ public:
                               bool keepRelative = false);
   static String TranslateCommand(CStrRef cmd);
   static Variant Open(CStrRef filename, CStrRef mode,
-                      int options = 0, CVarRef context = null);
+                      int options = 0, CVarRef context = uninit_null());
 
   static bool IsVirtualDirectory(CStrRef filename);
   static bool IsPlainFilePath(CStrRef filename);

hphp/runtime/base/file/user_file.cpp

@@ -104,7 +104,7 @@ Variant UserFile::invoke(const VM::Func *func, CStrRef name,
   // No explicitly defined function, no __call() magic method
   // Give up.
   if (!func && !m_Call) {
-    return null;
+    return uninit_null();
   }
 
   switch(g_vmContext->lookupObjMethod(func, m_cls, name.get())) {
@@ -133,18 +133,18 @@ Variant UserFile::invoke(const VM::Func *func, CStrRef name,
       // We're not calling staticly, so this result is unhelpful
       // Also, it's never produced by lookupObjMethod, so it'll
       // never happen, but we must handle all enums
-      return null;
+      return uninit_null();
 
     case MethodLookup::MethodFoundNoThis:
       // Should never happen (Attr::Static check in ctor)
       assert(false);
       raise_error("%s::%s() must not be declared static",
                   m_cls->name()->data(), name.data());
-      return null;
+      return uninit_null();
   }
 
   NOT_REACHED();
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/base/file/user_file.h

@@ -26,7 +26,7 @@ class UserFile : public File {
 public:
   DECLARE_OBJECT_ALLOCATION(UserFile);
 
-  UserFile(VM::Class *cls, int options = 0, CVarRef context = null);
+  UserFile(VM::Class *cls, int options = 0, CVarRef context = uninit_null());
   virtual ~UserFile();
 
   static StaticString s_class_name;

hphp/runtime/base/object_data.cpp

@@ -290,7 +290,7 @@ inline Variant ObjectData::o_getImpl(CStrRef propName, int flags,
     return o_getError(propName, context);
   }
 
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::o_get(CStrRef propName, bool error /* = true */,
@@ -317,7 +317,7 @@ Variant ObjectData::o_getPublic(CStrRef propName, bool error /* = true */) {
     return o_getError(propName, null_string);
   }
 
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::o_getUnchecked(CStrRef propName,
@@ -612,7 +612,7 @@ Variant ObjectData::o_invoke(CStrRef s, CArrRef params,
     if (!f) {
       // Bail if we couldn't find the method or __call
       o_invoke_failed(o_getClassName().data(), s.data(), fatal);
-      return null;
+      return uninit_null();
     }
     // We found __call! Stash the original name into invName.
     assert(!(f->attrs() & HPHP::VM::AttrStatic));
@@ -678,7 +678,7 @@ Variant ObjectData::o_invoke_ex(CStrRef clsname, CStrRef s,
   HPHP::VM::Class* cls = VM::Unit::lookupClass(clsname.get());
   if (!cls || !getVMClass()->classof(cls)) {
     o_invoke_failed(clsname.data(), s.data(), fatal);
-    return null;
+    return uninit_null();
   }
   StringData* invName = nullptr;
   // XXX The lookup below doesn't take context into account, so it will lead
@@ -697,7 +697,7 @@ Variant ObjectData::o_invoke_ex(CStrRef clsname, CStrRef s,
     if (!f) {
       // Bail if we couldn't find the method or __call
       o_invoke_failed(clsname.data(), s.data(), fatal);
-      return null;
+      return uninit_null();
     }
     // We found __call! Stash the original name into invName.
     assert(!(f->attrs() & HPHP::VM::AttrStatic));
@@ -776,7 +776,7 @@ void ObjectData::serializeImpl(VariableSerializer *serializer) const {
       handleSleep = const_cast<ObjectData*>(this)->php_sleep(ret);
     } catch (...) {
       raise_warning("%s::sleep() throws exception", o_getClassName().data());
-      ret = null;
+      ret = uninit_null();
       handleSleep = true;
     }
   }
@@ -799,7 +799,7 @@ void ObjectData::serializeImpl(VariableSerializer *serializer) const {
         } else {
           raise_warning("\"%s\" returned as member variable from "
               "__sleep() but does not exist", name.data());
-          wanted.set(name, null);
+          wanted.set(name, uninit_null());
         }
       }
       serializer->setObjectInfo(o_getClassName(), o_getId(), 'O');
@@ -829,7 +829,7 @@ void ObjectData::serializeImpl(VariableSerializer *serializer) const {
         raise_warning("serialize(): __sleep should return an array only "
                       "containing the names of instance-variables to "
                       "serialize");
-        null.serialize(serializer);
+        uninit_null().serialize(serializer);
       }
     }
   } else {
@@ -862,11 +862,11 @@ ObjectData *ObjectData::clone() {
 Variant ObjectData::o_getError(CStrRef prop, CStrRef context) {
   raise_notice("Undefined property: %s::$%s", o_getClassName().data(),
                prop.data());
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::o_setError(CStrRef prop, CStrRef context) {
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -875,22 +875,22 @@ Variant ObjectData::o_setError(CStrRef prop, CStrRef context) {
 
 Variant ObjectData::t___destruct() {
   // do nothing
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::t___call(Variant v_name, Variant v_arguments) {
   // do nothing
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::t___set(Variant v_name, Variant v_value) {
   // not called
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::t___get(Variant v_name) {
   // not called
-  return null;
+  return uninit_null();
 }
 
 Variant *ObjectData::___lval(Variant v_name) {
@@ -902,7 +902,7 @@ Variant ObjectData::offsetGet(Variant key) {
   const VM::Func* method = m_cls->lookupMethod(s_offsetGet.get());
   assert(method);
   if (!method) {
-    return null;
+    return uninit_null();
   }
   Variant v;
   g_vmContext->invokeFunc((TypedValue*)(&v), method,
@@ -916,7 +916,7 @@ bool ObjectData::t___isset(Variant v_name) {
 
 Variant ObjectData::t___unset(Variant v_name) {
   // not called
-  return null;
+  return uninit_null();
 }
 
 bool ObjectData::o_propExists(CStrRef s, CStrRef context /* = null_string */) {
@@ -926,12 +926,12 @@ bool ObjectData::o_propExists(CStrRef s, CStrRef context /* = null_string */) {
 
 Variant ObjectData::t___sleep() {
   clearAttribute(HasSleep);
-  return null;
+  return uninit_null();
 }
 
 Variant ObjectData::t___wakeup() {
   // do nothing
-  return null;
+  return uninit_null();
 }
 
 String ObjectData::t___tostring() {
@@ -942,7 +942,7 @@ String ObjectData::t___tostring() {
 
 Variant ObjectData::t___clone() {
   // do nothing
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/base/program_functions.cpp

@@ -225,7 +225,7 @@ void register_variable(Variant &variables, char *name, CVarRef value,
 
       if (!index) {
         symtable->append(Array::Create());
-        gpc_elements.push_back(null);
+        gpc_elements.push_back(uninit_null());
         gpc_elements.back().assignRef(
           symtable->lvalAt((int)symtable->toArray().size() - 1));
       } else {
@@ -234,7 +234,7 @@ void register_variable(Variant &variables, char *name, CVarRef value,
         if (v.isNull() || !v.is(KindOfArray)) {
           symtable->set(key, Array::Create());
         }
-        gpc_elements.push_back(null);
+        gpc_elements.push_back(uninit_null());
         gpc_elements.back().assignRef(symtable->lvalAt(key));
       }
       symtable = &gpc_elements.back();
@@ -491,7 +491,7 @@ void execute_command_line_begin(int argc, char **argv, int xhprof) {
   }
 
   if (xhprof) {
-    f_xhprof_enable(xhprof, null);
+    f_xhprof_enable(xhprof, uninit_null());
   }
 }
 
@@ -1283,7 +1283,7 @@ ExecutionContext *hphp_context_init() {
 bool hphp_invoke_simple(const std::string &filename,
                         bool warmupOnly /* = false */) {
   bool error; string errorMsg;
-  return hphp_invoke(g_context.getNoCheck(), filename, false, null_array, null,
+  return hphp_invoke(g_context.getNoCheck(), filename, false, null_array, uninit_null(),
                      "", "", error, errorMsg, true, warmupOnly);
 }
 

hphp/runtime/base/server/http_request_handler.cpp

@@ -312,7 +312,7 @@ bool HttpRequestHandler::executePHPRequest(Transport *transport,
 
   bool error = false;
   std::string errorMsg = "Internal Server Error";
-  ret = hphp_invoke(context, file, false, Array(), null,
+  ret = hphp_invoke(context, file, false, Array(), uninit_null(),
                     RuntimeOption::RequestInitFunction,
                     RuntimeOption::RequestInitDocument,
                     error, errorMsg);
@@ -339,7 +339,7 @@ bool HttpRequestHandler::executePHPRequest(Transport *transport,
       context->obEndAll();
       context->obStart();
       context->obProtect(true);
-      ret = hphp_invoke(context, errorPage, false, Array(), null,
+      ret = hphp_invoke(context, errorPage, false, Array(), uninit_null(),
                         RuntimeOption::RequestInitFunction,
                         RuntimeOption::RequestInitDocument,
                         error, errorMsg);

hphp/runtime/base/server/rpc_request_handler.cpp

@@ -247,7 +247,7 @@ bool RPCRequestHandler::executePHPFunction(Transport *transport,
       if (!forbidden) {
         rpcFile = canonicalize_path(rpcFile, "", 0);
         rpcFile = getSourceFilename(rpcFile, sourceRootInfo);
-        ret = hphp_invoke(m_context, rpcFile, false, Array(), null,
+        ret = hphp_invoke(m_context, rpcFile, false, Array(), uninit_null(),
                           reqInitFunc, reqInitDoc, error, errorMsg, runOnce);
       }
       // no need to do the initialization for a second time

hphp/runtime/base/server/transport.cpp

@@ -37,7 +37,7 @@ namespace HPHP {
 Transport::Transport()
   : m_instructions(0), m_url(nullptr), m_postData(nullptr), m_postDataParsed(false),
     m_chunkedEncoding(false), m_headerSent(false),
-    m_headerCallback(null), m_headerCallbackDone(false),
+    m_headerCallback(uninit_null()), m_headerCallbackDone(false),
     m_responseCode(-1), m_firstHeaderSet(false), m_firstHeaderLine(0),
     m_responseSize(0), m_responseTotalSize(0), m_responseSentSize(0),
     m_flushTimeUs(0), m_sendContentType(true),

hphp/runtime/base/time/timezone.cpp

@@ -166,7 +166,7 @@ Array TimeZone::GetAbbreviations() {
     if (entry->full_tz_name) {
       element.set("timezone_id", String(entry->full_tz_name, AttachLiteral));
     } else {
-      element.set("timezone_id", null);
+      element.set("timezone_id", uninit_null());
     }
 
     ret.lvalAt(entry->name).append(element);

hphp/runtime/base/type_object.cpp

@@ -103,7 +103,7 @@ bool Object::more(CObjRef v2) const {
 
 static Variant warn_non_object() {
   raise_warning("Cannot access property on non-object");
-  return null;
+  return uninit_null();
 }
 
 Variant Object::o_get(CStrRef propName, bool error /* = true */,

hphp/runtime/base/type_variant.cpp

@@ -2399,7 +2399,7 @@ Variant &Variant::lvalAt() {
       if (obj->isCollection()) {
         raise_error("Cannot use [] for reading");
       }
-      Array params = CREATE_VECTOR1(null);
+      Array params = CREATE_VECTOR1(uninit_null());
       Variant& ret = lvalBlackHole();
       ret = m_data.pobj->o_invoke(s_offsetGet, params);
       raise_warning("Indirect modification of overloaded element of %s has "
@@ -2473,7 +2473,7 @@ Variant Variant::o_set(CStrRef propName, CVarRef val,
   } else {
     // Raise a warning
     raise_warning("Attempt to assign property of non-object");
-    return null;
+    return uninit_null();
   }
   return m_data.pobj->o_set(propName, val, context);
 }
@@ -2488,7 +2488,7 @@ Variant Variant::o_setRef(CStrRef propName, CVarRef val,
   } else {
     // Raise a warning
     raise_warning("Attempt to assign property of non-object");
-    return null;
+    return uninit_null();
   }
   return m_data.pobj->o_setRef(propName, val, context);
 }
@@ -2502,7 +2502,7 @@ Variant Variant::o_setPublic(CStrRef propName, CVarRef val) {
   } else {
     // Raise a warning
     raise_warning("Attempt to assign property of non-object");
-    return null;
+    return uninit_null();
   }
   return m_data.pobj->o_setPublic(propName, val);
 }
@@ -2516,7 +2516,7 @@ Variant Variant::o_setPublicRef(CStrRef propName, CVarRef val) {
   } else {
     // Raise a warning
     raise_warning("Attempt to assign property of non-object");
-    return null;
+    return uninit_null();
   }
   return m_data.pobj->o_setPublicRef(propName, val);
 }
@@ -2697,7 +2697,7 @@ CVarRef Variant::append(CVarRef v) {
       if (LIKELY(obj->isCollection())) {
         collectionOffsetAppend(obj, v);
       } else {
-        Array params = CREATE_VECTOR2(null, v);
+        Array params = CREATE_VECTOR2(uninit_null(), v);
         obj->o_invoke(s_offsetSet, params);
       }
       break;
@@ -2826,7 +2826,7 @@ CVarRef Variant::appendRef(CVarRef v) {
       if (LIKELY(obj->isCollection())) {
         raise_error("Collection elements cannot be taken by reference");
       } else {
-        obj->o_invoke_few_args(s_offsetSet, -1, 2, null, v);
+        obj->o_invoke_few_args(s_offsetSet, -1, 2, uninit_null(), v);
       }
     }
   case KindOfStaticString:

hphp/runtime/base/type_variant.h

@@ -72,8 +72,6 @@ class MutableArrayIter;
  *   pref    strong    x (pointer)                      x
  */
 
-#define null ((Variant()))
-
 #ifdef HHVM_GC
 typedef GCRootTracker<Variant> VariantBase;
 #else
@@ -1565,6 +1563,10 @@ inline const Variant Array::operator[](CVarRef key) const {
   return rvalAt(key);
 }
 
+inline Variant uninit_null() {
+  return Variant();
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 }
 

hphp/runtime/base/variable_unserializer.cpp

@@ -66,7 +66,7 @@ void VariableUnserializer::read(char *buf, uint n) {
 }
 
 Variant &VariableUnserializer::addVar() {
-  m_vars.push_back(null);
+  m_vars.push_back(uninit_null());
   return m_vars.back();
 }
 

hphp/runtime/base/zend/zend_collator.cpp

@@ -350,7 +350,7 @@ static Variant collator_convert_object_to_string(CVarRef obj) {
   if (U_FAILURE(status)) {
     raise_warning("Error casting object to string in "
                   "collator_convert_object_to_string()");
-    return null;
+    return uninit_null();
   }
   return ustr;
 }

hphp/runtime/base/zend/zend_scanf.cpp

@@ -277,7 +277,7 @@ static inline void scan_set_error_return(int numVars, Variant &return_value) {
   if (numVars) {
     return_value = SCAN_ERROR_EOF; /* EOF marker */
   } else {
-    return_value = null;
+    return_value = uninit_null();
   }
 }
 

hphp/runtime/eval/debugger/cmd/cmd_machine.cpp

@@ -284,7 +284,7 @@ bool CmdMachine::onServer(DebuggerProxy *proxy) {
   if (m_body == "rpc") {
     String host = m_rpcConfig["host"].toString();
     if (host.empty()) {
-      register_intercept("", false, null);
+      register_intercept("", false, uninit_null());
     } else {
       int port = m_rpcConfig["port"].toInt32();
       LibEventHttpClient::SetCache(host.data(), port, 1);

hphp/runtime/eval/debugger/cmd/cmd_print.cpp

@@ -148,7 +148,7 @@ void CmdPrint::recvImpl(DebuggerThriftBuffer &thrift) {
     thrift.read(sdata);
     int error = DebuggerWireHelpers::WireUnserialize(sdata, m_ret);
     if (error) {
-      m_ret = null;
+      m_ret = uninit_null();
     }
     if (error == DebuggerWireHelpers::HitLimit) {
       m_wireError = "Hit unserialization limit. "

hphp/runtime/eval/debugger/debugger_proxy.cpp

@@ -347,7 +347,7 @@ Variant DebuggerProxy::ExecutePHP(const std::string &php, String &output,
   if (log) {
     Logger::SetThreadHook(append_stderr, &sb);
   }
-  ret = null;
+  ret = uninit_null();
   g_context->setStdout(nullptr, nullptr);
   g_context->swapOutputBuffer(save);
   if (log) {

hphp/runtime/eval/debugger/dummy_sandbox.cpp

@@ -114,7 +114,7 @@ void DummySandbox::run() {
                      doc.c_str(), cwd);
         bool error; string errorMsg;
         bool ret = hphp_invoke(g_context.getNoCheck(), doc, false, null_array,
-                               null, "", "", error, errorMsg, true, false,
+                               uninit_null(), "", "", error, errorMsg, true, false,
                                true);
         if (!ret || error) {
           msg += "Unable to pre-load " + doc;

hphp/runtime/ext/JSON_parser.cpp

@@ -395,7 +395,7 @@ static void json_create_zval(Variant &z, StringBuffer &buf, int type) {
     z = (buf.data() && (*buf.data() == 't'));
     break;
   default:
-    z = null;
+    z = uninit_null();
     break;
   }
 }

hphp/runtime/ext/ext_apc.cpp

@@ -422,7 +422,7 @@ void const_load_impl(struct cache_info *info,
         switch (*v++) {
         case 0: value = false; break;
         case 1: value = true; break;
-        case 2: value = null; break;
+        case 2: value = uninit_null(); break;
         default:
           throw Exception("bad apc archive, unknown char type");
         }
@@ -526,7 +526,7 @@ void apc_load_impl(struct cache_info *info,
         switch (*v++) {
         case 0: s.constructPrime(false, item); break;
         case 1: s.constructPrime(true , item); break;
-        case 2: s.constructPrime(null , item); break;
+        case 2: s.constructPrime(uninit_null() , item); break;
         default:
           throw Exception("bad apc archive, unknown char type");
         }
@@ -656,7 +656,7 @@ void const_load_impl_compressed
         switch (*v++) {
         case 0: value = false; break;
         case 1: value = true; break;
-        case 2: value = null; break;
+        case 2: value = uninit_null(); break;
         default:
           throw Exception("bad const archive, unknown char type");
         }
@@ -802,7 +802,7 @@ void apc_load_impl_compressed
         switch (*v++) {
         case 0: s.constructPrime(false, item); break;
         case 1: s.constructPrime(true , item); break;
-        case 2: s.constructPrime(null , item); break;
+        case 2: s.constructPrime(uninit_null() , item); break;
         default:
           throw Exception("bad apc archive, unknown char type");
         }

hphp/runtime/ext/ext_apc.ext_hhvm.cpp

@@ -173,7 +173,7 @@ TypedValue * fg1_apc_fetch(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count)
 TypedValue * fg1_apc_fetch(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToInt64InPlace(args-2);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   fh_apc_fetch((rv), (args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -185,7 +185,7 @@ TypedValue* fg_apc_fetch(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 3LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfInt64)) {
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         fh_apc_fetch((&(rv)), (args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -405,7 +405,7 @@ TypedValue * fg1_apc_inc(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_apc_inc((rv), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -417,7 +417,7 @@ TypedValue* fg_apc_inc(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 3 || (args-3)->m_type == KindOfInt64) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_apc_inc((&(rv)), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);
@@ -475,7 +475,7 @@ TypedValue * fg1_apc_dec(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_apc_dec((rv), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -487,7 +487,7 @@ TypedValue* fg_apc_dec(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 3 || (args-3)->m_type == KindOfInt64) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_apc_dec((&(rv)), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);

hphp/runtime/ext/ext_apc.h

@@ -27,11 +27,11 @@ namespace HPHP {
 
 bool f_apc_add(CStrRef key, CVarRef var, int64_t ttl = 0, int64_t cache_id = 0);
 bool f_apc_store(CStrRef key, CVarRef var, int64_t ttl = 0, int64_t cache_id = 0);
-Variant f_apc_fetch(CVarRef key, VRefParam success = null, int64_t cache_id = 0);
+Variant f_apc_fetch(CVarRef key, VRefParam success = uninit_null(), int64_t cache_id = 0);
 Variant f_apc_delete(CVarRef key, int64_t cache_id = 0);
 bool f_apc_clear_cache(int64_t cache_id = 0);
-Variant f_apc_inc(CStrRef key, int64_t step = 1, VRefParam success = null, int64_t cache_id = 0);
-Variant f_apc_dec(CStrRef key, int64_t step = 1, VRefParam success = null, int64_t cache_id = 0);
+Variant f_apc_inc(CStrRef key, int64_t step = 1, VRefParam success = uninit_null(), int64_t cache_id = 0);
+Variant f_apc_dec(CStrRef key, int64_t step = 1, VRefParam success = uninit_null(), int64_t cache_id = 0);
 bool f_apc_cas(CStrRef key, int64_t old_cas, int64_t new_cas, int64_t cache_id = 0);
 Variant f_apc_exists(CVarRef key, int64_t cache_id = 0);
 
@@ -68,10 +68,10 @@ inline bool f_apc_bin_load(CStrRef data, int64_t flags = 0, int64_t cache_id = 0
 }
 inline Variant f_apc_bin_dumpfile(int64_t cache_id, CVarRef filter,
                                   CStrRef filename, int64_t flags = 0,
-                                  CObjRef context = null) {
+                                  CObjRef context = uninit_null()) {
   throw NotSupportedException(__func__, "feature not supported");
 }
-inline bool f_apc_bin_loadfile(CStrRef filename, CObjRef context = null,
+inline bool f_apc_bin_loadfile(CStrRef filename, CObjRef context = uninit_null(),
                                int64_t flags = 0, int64_t cache_id = 0) {
   throw NotSupportedException(__func__, "feature not supported");
 }

hphp/runtime/ext/ext_array.cpp

@@ -74,7 +74,7 @@ using HPHP::VM::Transl::CallerFrame;
 
 #define getCheckedArrayRet(input, fail) \
   getCheckedArrayRetType(input, fail, CArrRef)
-#define getCheckedArray(input) getCheckedArrayRet(input, null)
+#define getCheckedArray(input) getCheckedArrayRet(input, uninit_null())
 
 Variant f_array_change_key_case(CVarRef input, bool upper /* = false */) {
   getCheckedArrayRet(input, false);
@@ -118,7 +118,7 @@ Variant f_array_filter(CVarRef input, CVarRef callback /* = null_variant */) {
   ctx.func = vm_decode_function(callback, cf(), false, ctx.this_, ctx.cls,
                                 ctx.invName);
   if (ctx.func == NULL) {
-    return null;
+    return uninit_null();
   }
   return ArrayUtil::Filter(arr_input, filter_func, &ctx);
 }
@@ -189,7 +189,7 @@ Variant f_array_map(int _argc, CVarRef callback, CVarRef arr1, CArrRef _argv /*
   Array inputs;
   if (!arr1.isArray()) {
     throw_bad_array_exception();
-    return null;
+    return uninit_null();
   }
   inputs.append(arr1);
   if (!_argv.empty()) {
@@ -255,7 +255,7 @@ Variant f_array_merge(int _argc, CVarRef array1,
     Variant v = iter.second();
     if (!v.isArray()) {
       throw_bad_array_exception();
-      return null;
+      return uninit_null();
     }
     CArrRef arr_v = v.asCArrRef();
     php_array_merge(ret, arr_v);
@@ -274,7 +274,7 @@ Variant f_array_merge_recursive(int _argc, CVarRef array1,
     Variant v = iter.second();
     if (!v.isArray()) {
       throw_bad_array_exception();
-      return null;
+      return uninit_null();
     }
     CArrRef arr_v = v.asCArrRef();
     php_array_merge_recursive(seen, false, ret, arr_v);
@@ -377,7 +377,7 @@ Variant f_array_product(CVarRef array) {
 }
 
 Variant f_array_push(int _argc, VRefParam array, CVarRef var, CArrRef _argv /* = null_array */) {
-  getCheckedArrayRetType(array, null, Array &);
+  getCheckedArrayRetType(array, uninit_null(), Array &);
   arr_array.append(var);
   for (ArrayIter iter(_argv); iter; ++iter) {
     arr_array.append(iter.second());
@@ -406,7 +406,7 @@ Variant f_array_reduce(CVarRef input, CVarRef callback,
   ctx.func = vm_decode_function(callback, cf(), false, ctx.this_, ctx.cls,
                                 ctx.invName);
   if (ctx.func == NULL) {
-    return null;
+    return uninit_null();
   }
   return ArrayUtil::Reduce(arr_input, reduce_func, &ctx, initial);
 }
@@ -513,7 +513,7 @@ bool f_array_walk_recursive(VRefParam input, CVarRef funcname,
   ctx.func = vm_decode_function(funcname, cf(), false, ctx.this_, ctx.cls,
                                 ctx.invName);
   if (ctx.func == NULL) {
-    return null;
+    return uninit_null();
   }
   PointerSet seen;
   ArrayUtil::Walk(input, walk_func, &ctx, true, &seen, userdata);
@@ -530,7 +530,7 @@ bool f_array_walk(VRefParam input, CVarRef funcname,
   ctx.func = vm_decode_function(funcname, cf(), false, ctx.this_, ctx.cls,
                                 ctx.invName);
   if (ctx.func == NULL) {
-    return null;
+    return uninit_null();
   }
   ArrayUtil::Walk(input, walk_func, &ctx, false, NULL, userdata);
   return true;

hphp/runtime/ext/ext_closure.cpp

@@ -28,7 +28,7 @@ void c_Closure::t___construct() {}
 
 Variant c_Closure::t___invoke(int _argc, CArrRef _argv) {
   always_assert(false);
-  return null;
+  return uninit_null();
 }
 
 bool c_Closure::php_sleep(Variant &ret) {

hphp/runtime/ext/ext_collections.cpp

@@ -130,7 +130,7 @@ void c_Vector::t___construct(CVarRef iterable /* = null_variant */) {
 }
 
 Variant c_Vector::t___destruct() {
-  return null;
+  return uninit_null();
 }
 
 void c_Vector::grow() {
@@ -278,7 +278,7 @@ Variant c_Vector::t_at(CVarRef key) {
     return tvAsCVarRef(at(key.toInt64()));
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 Variant c_Vector::t_get(CVarRef key) {
@@ -287,11 +287,11 @@ Variant c_Vector::t_get(CVarRef key) {
     if (tv) {
       return tvAsCVarRef(tv);
     } else {
-      return null;
+      return uninit_null();
     }
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 bool c_Vector::t_contains(CVarRef key) {
@@ -883,7 +883,7 @@ void c_Map::t___construct(CVarRef iterable /* = null_variant */) {
 }
 
 Variant c_Map::t___destruct() {
-  return null;
+  return uninit_null();
 }
 
 Array c_Map::toArrayImpl() const {
@@ -957,7 +957,7 @@ Variant c_Map::t_at(CVarRef key) {
     return tvAsCVarRef(at(key.getStringData()));
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 Variant c_Map::t_get(CVarRef key) {
@@ -966,18 +966,18 @@ Variant c_Map::t_get(CVarRef key) {
     if (tv) {
       return tvAsCVarRef(tv);
     } else {
-      return null;
+      return uninit_null();
     }
   } else if (key.isString()) {
     TypedValue* tv = get(key.getStringData());
     if (tv) {
       return tvAsCVarRef(tv);
     } else {
-      return null;
+      return uninit_null();
     }
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 Object c_Map::t_set(CVarRef key, CVarRef value) {
@@ -1793,7 +1793,7 @@ void c_StableMap::t___construct(CVarRef iterable /* = null_variant */) {
 }
 
 Variant c_StableMap::t___destruct() {
-  return null;
+  return uninit_null();
 }
 
 Array c_StableMap::toArrayImpl() const {
@@ -1884,7 +1884,7 @@ Variant c_StableMap::t_at(CVarRef key) {
     return tvAsCVarRef(at(key.getStringData()));
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 Variant c_StableMap::t_get(CVarRef key) {
@@ -1893,18 +1893,18 @@ Variant c_StableMap::t_get(CVarRef key) {
     if (tv) {
       return tvAsCVarRef(tv);
     } else {
-      return null;
+      return uninit_null();
     }
   } else if (key.isString()) {
     TypedValue* tv = get(key.getStringData());
     if (tv) {
       return tvAsCVarRef(tv);
     } else {
-      return null;
+      return uninit_null();
     }
   }
   throwBadKeyType();
-  return null;
+  return uninit_null();
 }
 
 Object c_StableMap::t_set(CVarRef key, CVarRef value) {

hphp/runtime/ext/ext_collections.h

@@ -61,10 +61,10 @@ class c_Vector : public ExtObjectDataFlags<ObjectData::VectorAttrInit|
   public: bool t_contains(CVarRef key);
   public: Object t_removeat(CVarRef key);
   public: Array t_toarray();
-  public: void t_sort(CVarRef col = null);
+  public: void t_sort(CVarRef col = uninit_null());
   public: void t_reverse();
-  public: void t_splice(CVarRef offset, CVarRef len = null,
-                        CVarRef replacement = null);
+  public: void t_splice(CVarRef offset, CVarRef len = uninit_null(),
+                        CVarRef replacement = uninit_null());
   public: int64_t t_linearsearch(CVarRef search_value);
   public: void t_shuffle();
   public: Object t_getiterator();
@@ -82,9 +82,9 @@ class c_Vector : public ExtObjectDataFlags<ObjectData::VectorAttrInit|
     return ti_fromvector("vector", vec);
   }
   public: static Variant ti_slice(const char* cls, CVarRef vec, CVarRef offset,
-                                  CVarRef len = null);
+                                  CVarRef len = uninit_null());
   public: static Variant t_slice(CVarRef vec, CVarRef offset,
-                                 CVarRef len = null) {
+                                 CVarRef len = uninit_null()) {
     return ti_slice("vector", vec, offset, len);
   }
 

hphp/runtime/ext/ext_continuation.cpp

@@ -199,7 +199,7 @@ String c_Continuation::t_getorigfuncname() {
 Variant c_Continuation::t___clone() {
   throw_fatal(
       "Trying to clone an uncloneable object of class Continuation");
-  return null;
+  return uninit_null();
 }
 
 HphpArray* c_Continuation::getStaticLocals() {
@@ -250,7 +250,7 @@ void c_DummyContinuation::t___construct() {
 
 Variant c_DummyContinuation::t_current() {
   throw_fatal("Tring to use a DummyContinuation");
-  return null;
+  return uninit_null();
 }
 
 int64_t c_DummyContinuation::t_key() {

hphp/runtime/ext/ext_continuation.h

@@ -47,7 +47,7 @@ class c_Continuation : public ExtObjectData {
   // need to implement
   public: c_Continuation(VM::Class* cls = c_Continuation::s_cls);
   public: ~c_Continuation();
-  public: void t___construct(int64_t func, int64_t extra, bool isMethod, CStrRef origFuncName, CVarRef obj = null, CArrRef args = null_array);
+  public: void t___construct(int64_t func, int64_t extra, bool isMethod, CStrRef origFuncName, CVarRef obj = uninit_null(), CArrRef args = null_array);
   public: void t_update(int64_t label, CVarRef value);
   public: void t_done();
   public: int64_t t_getlabel();

hphp/runtime/ext/ext_curl.cpp

@@ -604,7 +604,7 @@ public:
       m_exception = e.clone();
       m_phpException = false;
     }
-    return null;
+    return uninit_null();
   }
 
   static size_t curl_read(char *data, size_t size, size_t nmemb, void *ctx) {
@@ -833,7 +833,7 @@ Variant f_curl_getinfo(CObjRef ch, int opt /* = 0 */) {
       if (s_code != NULL) {
         ret.set("content_type", String(s_code, CopyString));
       } else {
-        ret.set("content_type", null);
+        ret.set("content_type", uninit_null());
       }
     }
     if (curl_easy_getinfo(cp, CURLINFO_HTTP_CODE, &l_code) == CURLE_OK) {
@@ -961,7 +961,7 @@ Variant f_curl_getinfo(CObjRef ch, int opt /* = 0 */) {
     }
   }
 
-  return null;
+  return uninit_null();
 }
 
 Variant f_curl_errno(CObjRef ch) {
@@ -977,7 +977,7 @@ Variant f_curl_error(CObjRef ch) {
 Variant f_curl_close(CObjRef ch) {
   CHECK_RESOURCE(curl);
   curl->close();
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -1083,7 +1083,7 @@ StaticString CurlMultiResource::s_class_name("cURL Multi Handle");
   CurlMultiResource *curlm = mh.getTyped<CurlMultiResource>(true, true); \
   if (curlm == NULL) {                                                  \
     raise_warning("expects parameter 1 to be cURL multi resource");     \
-    return null;                                                        \
+    return uninit_null();                                                        \
   }                                                                     \
 
 Object f_curl_multi_init() {
@@ -1234,7 +1234,7 @@ Variant f_curl_multi_info_read(CObjRef mh,
 Variant f_curl_multi_close(CObjRef mh) {
   CHECK_MULTI_RESOURCE(curlm);
   curlm->close();
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_curl.ext_hhvm.cpp

@@ -987,7 +987,7 @@ TypedValue * fg1_curl_multi_info_read(TypedValue* rv, HPHP::VM::ActRec* ar, int6
 TypedValue * fg1_curl_multi_info_read(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToObjectInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   fh_curl_multi_info_read((rv), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -999,7 +999,7 @@ TypedValue* fg_curl_multi_info_read(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 2LL) {
       if ((args-0)->m_type == KindOfObject) {
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         fh_curl_multi_info_read((&(rv)), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 2);

hphp/runtime/ext/ext_curl.h

@@ -46,7 +46,7 @@ Variant f_curl_multi_exec(CObjRef mh, VRefParam still_running);
 Variant f_curl_multi_select(CObjRef mh, double timeout = 1.0);
 Variant f_fb_curl_multi_fdset(CObjRef mh, VRefParam read_fd_set, VRefParam write_fd_set, VRefParam exc_fd_set, VRefParam max_fd = null_object);
 Variant f_curl_multi_getcontent(CObjRef ch);
-Variant f_curl_multi_info_read(CObjRef mh, VRefParam msgs_in_queue = null);
+Variant f_curl_multi_info_read(CObjRef mh, VRefParam msgs_in_queue = uninit_null());
 Variant f_curl_multi_close(CObjRef mh);
 void f_evhttp_set_cache(CStrRef address, int max_conn, int port = 80);
 Variant f_evhttp_get(CStrRef url, CArrRef headers = null_array, int timeout = 5);

hphp/runtime/ext/ext_datetime.cpp

@@ -253,19 +253,19 @@ Variant c_DateInterval::t___get(Variant member) {
 
 Variant c_DateInterval::t___set(Variant member, Variant value) {
   if (member.isString()) {
-    if (member.same("y")) { m_di->setYears(value.toInt64());   return null; }
-    if (member.same("m")) { m_di->setMonths(value.toInt64());  return null; }
-    if (member.same("d")) { m_di->setDays(value.toInt64());    return null; }
-    if (member.same("h")) { m_di->setHours(value.toInt64());   return null; }
-    if (member.same("i")) { m_di->setMinutes(value.toInt64()); return null; }
-    if (member.same("s")) { m_di->setSeconds(value.toInt64()); return null; }
+    if (member.same("y")) { m_di->setYears(value.toInt64());   return uninit_null(); }
+    if (member.same("m")) { m_di->setMonths(value.toInt64());  return uninit_null(); }
+    if (member.same("d")) { m_di->setDays(value.toInt64());    return uninit_null(); }
+    if (member.same("h")) { m_di->setHours(value.toInt64());   return uninit_null(); }
+    if (member.same("i")) { m_di->setMinutes(value.toInt64()); return uninit_null(); }
+    if (member.same("s")) { m_di->setSeconds(value.toInt64()); return uninit_null(); }
     if (member.same("invert")) {
       m_di->setInverted(value.toBoolean());
-      return null;
+      return uninit_null();
     }
     if (member.same("days")) {
       m_di->setTotalDays(value.toInt64());
-      return null;
+      return uninit_null();
     }
   }
 

hphp/runtime/ext/ext_debugger.cpp

@@ -88,7 +88,7 @@ static DbgCltMap s_dbgCltMap;
 // if the DebuggerClient with the same name is already in use, return null
 Variant f_hphpd_get_client(CStrRef name /* = null */) {
   if (name.empty()) {
-    return null;
+    return uninit_null();
   }
   DebuggerClient *client = NULL;
   std::string nameStr = name->toCPPString();
@@ -102,7 +102,7 @@ Variant f_hphpd_get_client(CStrRef name /* = null */) {
     }
     if (!client->apiGrab()) {
       // already grabbed by another request
-      return null;
+      return uninit_null();
     }
   }
   p_DebuggerClient clt(NEWOBJ(c_DebuggerClient));
@@ -120,7 +120,7 @@ Variant f_hphpd_client_ctrl(CStrRef name, CStrRef op) {
         return q_DebuggerClient$$STATE_INVALID;
       } else {
         raise_warning("client %s does not exist", name.data());
-        return null;
+        return uninit_null();
       }
     }
     client = acc->second;
@@ -128,14 +128,14 @@ Variant f_hphpd_client_ctrl(CStrRef name, CStrRef op) {
   if (op.equal("interrupt")) {
     if (client->getClientState() < DebuggerClient::StateReadyForCommand) {
       raise_warning("client is not initialized");
-      return null;
+      return uninit_null();
     }
     if (client->getClientState() != DebuggerClient::StateBusy) {
       raise_warning("client is not in a busy state");
-      return null;
+      return uninit_null();
     }
     client->onSignal(SIGINT);
-    return null;
+    return uninit_null();
   } else if (op.equal("getstate")) {
     return client->getClientState();
   } else if (op.equal("reset")) {
@@ -152,7 +152,7 @@ Variant f_hphpd_client_ctrl(CStrRef name, CStrRef op) {
 
   raise_warning("unknown op %s", op.data());
 
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -479,19 +479,19 @@ Variant c_DebuggerClient::t_processcmd(CVarRef cmdName, CVarRef args) {
   if (!m_client ||
       m_client->getClientState() < DebuggerClient::StateReadyForCommand) {
     raise_warning("client is not initialized");
-    return null;
+    return uninit_null();
   }
   if (m_client->getClientState() != DebuggerClient::StateReadyForCommand) {
     raise_warning("client is not ready to take command");
-    return null;
+    return uninit_null();
   }
   if (!cmdName.isString()) {
     raise_warning("cmdName must be string");
-    return null;
+    return uninit_null();
   }
   if (!args.isNull() && !args.isArray()) {
     raise_warning("args must be null or array");
-    return null;
+    return uninit_null();
   }
 
   static const char *s_allowedCmds[] = {
@@ -513,7 +513,7 @@ Variant c_DebuggerClient::t_processcmd(CVarRef cmdName, CVarRef args) {
   }
   if (!allowed) {
     raise_warning("unsupported command %s", cmdName.toString().data());
-    return null;
+    return uninit_null();
   }
 
   m_client->setCommand(cmdName.toString().data());
@@ -555,7 +555,7 @@ Variant c_DebuggerClient::t_processcmd(CVarRef cmdName, CVarRef args) {
     return true;
   } catch (DebuggerProtocolException &e) {
     raise_warning("DebuggerProtocolException");
-    return null;
+    return uninit_null();
   }
 
   return m_client->getOutputArray();

hphp/runtime/ext/ext_debugger.ext_hhvm.cpp

@@ -178,7 +178,7 @@ TypedValue * fg1_hphpd_get_client(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t
 TypedValue * fg1_hphpd_get_client(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToStringInPlace(args-0);
-  String defVal0 = null;
+  String defVal0 = uninit_null();
   fh_hphpd_get_client((rv), (count > 0) ? (Value*)(args-0) : (Value*)(&defVal0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -190,7 +190,7 @@ TypedValue* fg_hphpd_get_client(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count <= 1LL) {
       if ((count <= 0 || IS_STRING_TYPE((args-0)->m_type))) {
-        String defVal0 = null;
+        String defVal0 = uninit_null();
         fh_hphpd_get_client((&(rv)), (count > 0) ? (Value*)(args-0) : (Value*)(&defVal0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 1);

hphp/runtime/ext/ext_domdocument.cpp

@@ -1171,7 +1171,7 @@ static Variant php_dom_create_object(xmlNodePtr obj, p_DOMDocument doc,
   case XML_NOTATION_NODE:      clsname = "domnotation";              break;
   default:
     raise_warning("Unsupported node type: %d", obj->type);
-    return null;
+    return uninit_null();
   }
 
   if (doc.get() && doc->m_classmap.exists(clsname)) {
@@ -1191,7 +1191,7 @@ static Variant php_dom_create_object(xmlNodePtr obj, p_DOMDocument doc,
 static Variant create_node_object(xmlNodePtr node, p_DOMDocument doc,
                                   bool owner = false) {
   if (!node) {
-    return null;
+    return uninit_null();
   }
   Variant retval = php_dom_create_object(node, doc, owner);
   if (retval.isNull()) {
@@ -1304,7 +1304,7 @@ static Variant php_xpath_eval(c_DOMXPath * domxpath, CStrRef expr,
     ret = String((char*)xpathobjp->stringval, CopyString);
     break;
   default:
-    ret = null;
+    ret = uninit_null();
     break;
   }
   xmlXPathFreeObject(xpathobjp);
@@ -1461,7 +1461,7 @@ static xmlNode *php_dom_libxml_notation_iter(xmlHashTable *ht, int index) {
 
 Variant dummy_getter(CObjRef) {
   raise_error("Cannot read property");
-  return null;
+  return uninit_null();
 }
 
 void dummy_setter(CObjRef,CVarRef) {
@@ -1522,7 +1522,7 @@ public:
   xmlNodePtr nodep = domnode->m_node;                   \
   if (nodep == NULL) {                                  \
     php_dom_throw_error(INVALID_STATE_ERR, 0);          \
-    return null;                                        \
+    return uninit_null();                                        \
   }                                                     \
 
 #define CHECK_WRITE_NODE(nodep)                         \
@@ -1612,7 +1612,7 @@ static Variant domnode_nodevalue_read(CObjRef obj) {
     xmlFree(str);
     return retval;
   } else {
-    return null;
+    return uninit_null();
   }
 }
 
@@ -1661,7 +1661,7 @@ static Variant domnode_parentnode_read(CObjRef obj) {
 static Variant domnode_childnodes_read(CObjRef obj) {
   CHECK_NODE(nodep);
   if (!dom_node_children_valid(nodep)) {
-    return null;
+    return uninit_null();
   }
   c_DOMNodeList *retval = NEWOBJ(c_DOMNodeList)();
   retval->m_doc = domnode->doc();
@@ -1707,14 +1707,14 @@ static Variant domnode_attributes_read(CObjRef obj) {
     nodemap->m_nodetype = XML_ATTRIBUTE_NODE;
     return nodemap;
   }
-  return null;
+  return uninit_null();
 }
 
 static Variant domnode_ownerdocument_read(CObjRef obj) {
   CHECK_NODE(nodep);
   if (nodep->type == XML_DOCUMENT_NODE ||
       nodep->type == XML_HTML_DOCUMENT_NODE) {
-    return null;
+    return uninit_null();
   }
   return create_node_object((xmlNodePtr)nodep->doc, domnode->doc());
 }
@@ -1736,7 +1736,7 @@ static Variant domnode_namespaceuri_read(CObjRef obj) {
   if (str) {
     return String(str, CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 static Variant domnode_prefix_read(CObjRef obj) {
@@ -1829,7 +1829,7 @@ static Variant domnode_localname_read(CObjRef obj) {
       nodep->type == XML_NAMESPACE_DECL) {
     return String((char *)(nodep->name), CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 static Variant domnode_baseuri_read(CObjRef obj) {
@@ -1840,7 +1840,7 @@ static Variant domnode_baseuri_read(CObjRef obj) {
     xmlFree(baseuri);
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 static Variant domnode_textcontent_read(CObjRef obj) {
@@ -1898,7 +1898,7 @@ Variant c_DOMNode::t___get(Variant name) {
 
 Variant c_DOMNode::t___set(Variant name, Variant value) {
   domnode_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMNode::t___isset(Variant name) {
@@ -2204,14 +2204,14 @@ Variant c_DOMNode::t_lookupnamespaceuri(CStrRef namespaceuri) {
       nodep->type == XML_HTML_DOCUMENT_NODE) {
     nodep = xmlDocGetRootElement((xmlDocPtr) nodep);
     if (nodep == NULL) {
-      return null;
+      return uninit_null();
     }
   }
   nsptr = xmlSearchNs(nodep->doc, nodep, (xmlChar*)namespaceuri.data());
   if (nsptr && nsptr->href != NULL) {
     return String((char *)nsptr->href, CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNode::t_lookupprefix(CStrRef prefix) {
@@ -2232,7 +2232,7 @@ Variant c_DOMNode::t_lookupprefix(CStrRef prefix) {
     case XML_DOCUMENT_FRAG_NODE:
     case XML_DOCUMENT_TYPE_NODE:
     case XML_DTD_NODE:
-      return null;
+      return uninit_null();
     default:
       lookupp = nodep->parent;
     }
@@ -2244,7 +2244,7 @@ Variant c_DOMNode::t_lookupprefix(CStrRef prefix) {
       }
     }
   }
-  return null;
+  return uninit_null();
 }
 
 void c_DOMNode::t_normalize() {
@@ -2365,7 +2365,7 @@ Variant c_DOMNode::t_getnodepath() {
     xmlFree(value);
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -2375,7 +2375,7 @@ Variant c_DOMNode::t_getnodepath() {
   xmlAttrPtr attrp = (xmlAttrPtr)domattr->m_node;       \
   if (attrp == NULL) {                                  \
     php_dom_throw_error(INVALID_STATE_ERR, 0);          \
-    return null;                                        \
+    return uninit_null();                                        \
   }                                                     \
 
 #define CHECK_WRITE_ATTR(attrp)                         \
@@ -2424,7 +2424,7 @@ static Variant domattr_ownerelement_read(CObjRef obj) {
 
 static Variant domattr_schematypeinfo_read(CObjRef obj) {
   raise_warning("Not yet implemented");
-  return null;
+  return uninit_null();
 }
 
 static PropertyAccessor domattr_properties[] = {
@@ -2466,7 +2466,7 @@ Variant c_DOMAttr::t___get(Variant name) {
 
 Variant c_DOMAttr::t___set(Variant name, Variant value) {
   domattr_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMAttr::t___isset(Variant name) {
@@ -2534,7 +2534,7 @@ Variant c_DOMCharacterData::t___get(Variant name) {
 
 Variant c_DOMCharacterData::t___set(Variant name, Variant value) {
   domcharacterdata_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMCharacterData::t___isset(Variant name) {
@@ -2745,7 +2745,7 @@ Variant c_DOMText::t___get(Variant name) {
 
 Variant c_DOMText::t___set(Variant name, Variant value) {
   domtext_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMText::t___isset(Variant name) {
@@ -2817,7 +2817,7 @@ void c_DOMCDATASection::t___construct(CStrRef value) {
   xmlDocPtr docp = (xmlDocPtr)domdoc->m_node;                   \
   if (docp == NULL) {                                           \
     php_dom_throw_error(INVALID_STATE_ERR, 0);                  \
-    return null;                                                \
+    return uninit_null();                                                \
   }                                                             \
 
 #define CHECK_WRITE_DOC(docp)                                   \
@@ -2848,7 +2848,7 @@ static Variant dom_document_encoding_read(CObjRef obj) {
   if (encoding) {
     return String(encoding, CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 static void dom_document_encoding_write(CObjRef obj, CVarRef value) {
@@ -2892,7 +2892,7 @@ static Variant dom_document_version_read(CObjRef obj) {
   if (version) {
     return String(version, CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 static void dom_document_version_write(CObjRef obj, CVarRef value) {
@@ -2929,7 +2929,7 @@ static Variant dom_document_document_uri_read(CObjRef obj) {
   if (url) {
     return String(url, CopyString);
   }
-  return null;
+  return uninit_null();
 }
 
 static void dom_document_document_uri_write(CObjRef obj, CVarRef value) {
@@ -2942,7 +2942,7 @@ static void dom_document_document_uri_write(CObjRef obj, CVarRef value) {
 }
 
 static Variant dom_document_config_read(CObjRef obj) {
-  return null;
+  return uninit_null();
 }
 
 /* }}} */
@@ -3043,7 +3043,7 @@ Variant c_DOMDocument::t___get(Variant name) {
 
 Variant c_DOMDocument::t___set(Variant name, Variant value) {
   domdocument_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMDocument::t___isset(Variant name) {
@@ -3287,7 +3287,7 @@ Variant c_DOMDocument::t_getelementbyid(CStrRef elementid) {
     ret->m_node = attrp->parent;
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMDocument::t_getelementsbytagname(CStrRef name) {
@@ -3612,7 +3612,7 @@ bool c_DOMDocumentFragment::t_appendxml(CStrRef data) {
   xmlDtdPtr dtdptr = (xmlDtdPtr)domdoctype->m_node;                     \
   if (dtdptr == NULL) {                                                 \
     php_dom_throw_error(INVALID_STATE_ERR, 0);                          \
-    return null;                                                        \
+    return uninit_null();                                                        \
   }                                                                     \
 
 static Variant dom_documenttype_name_read(CObjRef obj) {
@@ -3706,7 +3706,7 @@ Variant c_DOMDocumentType::t___get(Variant name) {
 
 Variant c_DOMDocumentType::t___set(Variant name, Variant value) {
   domdocumenttype_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMDocumentType::t___isset(Variant name) {
@@ -3731,7 +3731,7 @@ static Variant dom_element_tag_name_read(CObjRef obj) {
 }
 
 static Variant dom_element_schema_type_info_read(CObjRef obj) {
-  return null;
+  return uninit_null();
 }
 
 static PropertyAccessor domelement_properties[] = {
@@ -3817,7 +3817,7 @@ Variant c_DOMElement::t___get(Variant name) {
 
 Variant c_DOMElement::t___set(Variant name, Variant value) {
   domelement_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMElement::t___isset(Variant name) {
@@ -4020,7 +4020,7 @@ Variant c_DOMElement::t_removeattributens(CStrRef namespaceuri,
   xmlNsPtr nsptr;
   if (dom_node_is_read_only(nodep)) {
     php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, doc()->m_stricterror);
-    return null;
+    return uninit_null();
   }
   attrp = xmlHasNsProp(nodep, (xmlChar*)localname.data(),
                        (xmlChar*)namespaceuri.data());
@@ -4036,7 +4036,7 @@ Variant c_DOMElement::t_removeattributens(CStrRef namespaceuri,
         nsptr->prefix = NULL;
       }
     } else {
-      return null;
+      return uninit_null();
     }
   }
   if (attrp && attrp->type != XML_ATTRIBUTE_DECL) {
@@ -4044,7 +4044,7 @@ Variant c_DOMElement::t_removeattributens(CStrRef namespaceuri,
     xmlUnlinkNode((xmlNodePtr)attrp);
     xmlFreeProp(attrp);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setattribute(CStrRef name, CStrRef value) {
@@ -4126,7 +4126,7 @@ Variant c_DOMElement::t_setattributenode(CObjRef newattr) {
     ret->m_node = (xmlNodePtr)existattrp;
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setattributenodens(CObjRef newattr) {
@@ -4167,7 +4167,7 @@ Variant c_DOMElement::t_setattributenodens(CObjRef newattr) {
     ret->m_node = (xmlNodePtr)existattrp;
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setattributens(CStrRef namespaceuri, CStrRef name,
@@ -4185,7 +4185,7 @@ Variant c_DOMElement::t_setattributens(CStrRef namespaceuri, CStrRef name,
   int stricterror = doc()->m_stricterror;
   if (dom_node_is_read_only(elemp)) {
     php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, stricterror);
-    return null;
+    return uninit_null();
   }
   errorcode = dom_check_qname((char*)name.data(), &localname, &prefix,
                               namespaceuri.size(), name.size());
@@ -4266,7 +4266,7 @@ Variant c_DOMElement::t_setattributens(CStrRef namespaceuri, CStrRef name,
   if (errorcode != 0) {
     php_dom_throw_error((dom_exception_code)errorcode, stricterror);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setidattribute(CStrRef name, bool isid) {
@@ -4274,7 +4274,7 @@ Variant c_DOMElement::t_setidattribute(CStrRef name, bool isid) {
   xmlAttrPtr attrp;
   if (dom_node_is_read_only(nodep)) {
     php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, doc()->m_stricterror);
-    return null;
+    return uninit_null();
   }
   attrp = xmlHasNsProp(nodep, (xmlChar*)name.data(), NULL);
   if (attrp == NULL || attrp->type == XML_ATTRIBUTE_DECL) {
@@ -4282,7 +4282,7 @@ Variant c_DOMElement::t_setidattribute(CStrRef name, bool isid) {
   } else {
     php_set_attribute_id(attrp, isid);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setidattributenode(CObjRef idattr, bool isid) {
@@ -4291,14 +4291,14 @@ Variant c_DOMElement::t_setidattributenode(CObjRef idattr, bool isid) {
   xmlAttrPtr attrp = (xmlAttrPtr)domattr->m_node;
   if (dom_node_is_read_only(nodep)) {
     php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, doc()->m_stricterror);
-    return null;
+    return uninit_null();
   }
   if (attrp->parent != nodep) {
     php_dom_throw_error(NOT_FOUND_ERR, doc()->m_stricterror);
   } else {
     php_set_attribute_id(attrp, isid);
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMElement::t_setidattributens(CStrRef namespaceuri,
@@ -4307,7 +4307,7 @@ Variant c_DOMElement::t_setidattributens(CStrRef namespaceuri,
   xmlAttrPtr attrp;
   if (dom_node_is_read_only(elemp)) {
     php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, doc()->m_stricterror);
-    return null;
+    return uninit_null();
   }
   attrp = xmlHasNsProp(elemp, (xmlChar*)localname.data(),
                        (xmlChar*)namespaceuri.data());
@@ -4316,7 +4316,7 @@ Variant c_DOMElement::t_setidattributens(CStrRef namespaceuri,
   } else {
     php_set_attribute_id(attrp, isid);
   }
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -4326,13 +4326,13 @@ Variant c_DOMElement::t_setidattributens(CStrRef namespaceuri,
   xmlEntity *nodep = (xmlEntity*)domentity->m_node;     \
   if (nodep == NULL) {                                  \
     php_dom_throw_error(INVALID_STATE_ERR, 0);          \
-    return null;                                        \
+    return uninit_null();                                        \
   }                                                     \
 
 static Variant dom_entity_public_id_read(CObjRef obj) {
   CHECK_ENTITY(nodep);
   if (nodep->etype != XML_EXTERNAL_GENERAL_UNPARSED_ENTITY) {
-    return null;
+    return uninit_null();
   }
   return String((char *)(nodep->ExternalID), CopyString);
 }
@@ -4340,7 +4340,7 @@ static Variant dom_entity_public_id_read(CObjRef obj) {
 static Variant dom_entity_system_id_read(CObjRef obj) {
   CHECK_ENTITY(nodep);
   if (nodep->etype != XML_EXTERNAL_GENERAL_UNPARSED_ENTITY) {
-    return null;
+    return uninit_null();
   }
   return String((char *)(nodep->SystemID), CopyString);
 }
@@ -4348,7 +4348,7 @@ static Variant dom_entity_system_id_read(CObjRef obj) {
 static Variant dom_entity_notation_name_read(CObjRef obj) {
   CHECK_ENTITY(nodep);
   if (nodep->etype != XML_EXTERNAL_GENERAL_UNPARSED_ENTITY) {
-    return null;
+    return uninit_null();
   }
   char *content = (char*)xmlNodeGetContent((xmlNodePtr) nodep);
   String ret(content, CopyString);
@@ -4357,7 +4357,7 @@ static Variant dom_entity_notation_name_read(CObjRef obj) {
 }
 
 static Variant dom_entity_actual_encoding_read(CObjRef obj) {
-  return null;
+  return uninit_null();
 }
 
 static void dom_entity_actual_encoding_write(CObjRef obj, CVarRef value) {
@@ -4365,7 +4365,7 @@ static void dom_entity_actual_encoding_write(CObjRef obj, CVarRef value) {
 }
 
 static Variant dom_entity_encoding_read(CObjRef obj) {
-  return null;
+  return uninit_null();
 }
 
 static void dom_entity_encoding_write(CObjRef obj, CVarRef value) {
@@ -4373,7 +4373,7 @@ static void dom_entity_encoding_write(CObjRef obj, CVarRef value) {
 }
 
 static Variant dom_entity_version_read(CObjRef obj) {
-  return null;
+  return uninit_null();
 }
 
 static void dom_entity_version_write(CObjRef obj, CVarRef value) {
@@ -4412,7 +4412,7 @@ Variant c_DOMEntity::t___get(Variant name) {
 
 Variant c_DOMEntity::t___set(Variant name, Variant value) {
   domentity_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMEntity::t___isset(Variant name) {
@@ -4448,7 +4448,7 @@ void c_DOMEntityReference::t___construct(CStrRef name) {
   xmlEntity *nodep = (xmlEntity*)domnotation->m_node;         \
   if (nodep == NULL) {                                        \
     php_dom_throw_error(INVALID_STATE_ERR, 0);                \
-    return null;                                              \
+    return uninit_null();                                              \
   }                                                           \
 
 static Variant dom_notation_public_id_read(CObjRef obj) {
@@ -4496,7 +4496,7 @@ Variant c_DOMNotation::t___get(Variant name) {
 
 Variant c_DOMNotation::t___set(Variant name, Variant value) {
   domnotation_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMNotation::t___isset(Variant name) {
@@ -4567,7 +4567,7 @@ Variant c_DOMProcessingInstruction::t___get(Variant name) {
 
 Variant c_DOMProcessingInstruction::t___set(Variant name, Variant value) {
   domprocessinginstruction_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMProcessingInstruction::t___isset(Variant name) {
@@ -4654,7 +4654,7 @@ Variant c_DOMNamedNodeMap::t_getnameditem(CStrRef name) {
     }
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNamedNodeMap::t_getnameditemns(CStrRef namespaceuri,
@@ -4692,7 +4692,7 @@ Variant c_DOMNamedNodeMap::t_getnameditemns(CStrRef namespaceuri,
     }
     return ret;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNamedNodeMap::t_item(int64_t index) {
@@ -4731,7 +4731,7 @@ Variant c_DOMNamedNodeMap::t_item(int64_t index) {
     }
   }
 
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNamedNodeMap::t___get(Variant name) {
@@ -4740,7 +4740,7 @@ Variant c_DOMNamedNodeMap::t___get(Variant name) {
 
 Variant c_DOMNamedNodeMap::t___set(Variant name, Variant value) {
   domnamednodemap_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMNamedNodeMap::t___isset(Variant name) {
@@ -4820,7 +4820,7 @@ Variant c_DOMNodeList::t___get(Variant name) {
 
 Variant c_DOMNodeList::t___set(Variant name, Variant value) {
   domnodelist_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMNodeList::t___isset(Variant name) {
@@ -5207,7 +5207,7 @@ Variant c_DOMXPath::t___get(Variant name) {
 
 Variant c_DOMXPath::t___set(Variant name, Variant value) {
   domxpath_properties_map.setter(name)(this, value);
-  return null;
+  return uninit_null();
 }
 
 bool c_DOMXPath::t___isset(Variant name) {
@@ -5249,7 +5249,7 @@ Variant c_DOMXPath::t_registerphpfunctions(CVarRef funcs /* = null */) {
   } else {
     m_registerPhpFunctions = 1;
   }
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -5346,7 +5346,7 @@ Variant c_DOMNodeIterator::t_key() {
 Variant c_DOMNodeIterator::t_next() {
   if (m_iter) {
     m_iter->next();
-    return null;
+    return uninit_null();
   }
 
   xmlNodePtr curnode = NULL;
@@ -5391,7 +5391,7 @@ err:
   } else {
     m_curobj.reset();
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNodeIterator::t_rewind() {
@@ -5399,7 +5399,7 @@ Variant c_DOMNodeIterator::t_rewind() {
   m_iter = NULL;
   m_index = -1;
   reset_iterator();
-  return null;
+  return uninit_null();
 }
 
 Variant c_DOMNodeIterator::t_valid() {
@@ -5418,11 +5418,11 @@ Variant c_DOMNodeIterator::t_valid() {
     pobj = obj.toObject().getTyped<c_DOM ##name>(true, true);   \
     if (pobj == NULL) {                                         \
       raise_warning("Expecting dom " #name " object");          \
-      return null;                                              \
+      return uninit_null();                                              \
     }                                                           \
   } else {                                                      \
     raise_warning("Expecting dom objects in parameters");       \
-    return null;                                                \
+    return uninit_null();                                                \
   }
 
 Variant f_dom_document_create_element(CVarRef obj, CStrRef name,
@@ -5503,7 +5503,7 @@ Variant f_dom_document_get_element_by_id(CVarRef obj, CStrRef elementid) {
 Variant f_dom_document_normalize_document(CVarRef obj) {
   DOM_GET_OBJ(Document);
   pobj->t_normalizedocument();
-  return null;
+  return uninit_null();
 }
 
 Variant f_dom_document_save(CVarRef obj, CStrRef file,
@@ -5593,7 +5593,7 @@ Variant f_dom_node_clone_node(CVarRef obj, bool deep /* = false */) {
 Variant f_dom_node_normalize(CVarRef obj) {
   DOM_GET_OBJ(Node);
   pobj->t_normalize();
-  return null;
+  return uninit_null();
 }
 
 Variant f_dom_node_is_supported(CVarRef obj, CStrRef feature,

hphp/runtime/ext/ext_domdocument.ext_hhvm.cpp

@@ -1341,7 +1341,7 @@ TypedValue * fg1_dom_node_insert_before(TypedValue* rv, HPHP::VM::ActRec* ar, in
   if ((args-1)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-1);
   }
-  Object defVal2 = null;
+  Object defVal2 = uninit_null();
   fh_dom_node_insert_before((rv), (args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -1353,7 +1353,7 @@ TypedValue* fg_dom_node_insert_before(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfObject) && (args-1)->m_type == KindOfObject) {
-        Object defVal2 = null;
+        Object defVal2 = uninit_null();
         fh_dom_node_insert_before((&(rv)), (args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -4055,7 +4055,7 @@ TypedValue* tg1_7DOMNode_insertBefore(TypedValue* rv, HPHP::VM::ActRec* ar, int6
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  Object defVal1 = null;
+  Object defVal1 = uninit_null();
   th_7DOMNode_insertBefore((rv), (this_), (Value*)(args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -4069,7 +4069,7 @@ TypedValue* tg_7DOMNode_insertBefore(HPHP::VM::ActRec *ar) {
     if (this_) {
       if (count >= 1LL && count <= 2LL) {
         if ((count <= 1 || (args-1)->m_type == KindOfObject) && (args-0)->m_type == KindOfObject) {
-          Object defVal1 = null;
+          Object defVal1 = uninit_null();
           th_7DOMNode_insertBefore((&(rv)), (this_), (Value*)(args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1));
           if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
           frame_free_locals_inl(ar, 2);

hphp/runtime/ext/ext_domdocument.h

@@ -50,7 +50,7 @@ Variant f_dom_document_schema_validate_file(CVarRef obj, CStrRef filename);
 Variant f_dom_document_schema_validate_xml(CVarRef obj, CStrRef source);
 Variant f_dom_document_relaxng_validate_file(CVarRef obj, CStrRef filename);
 Variant f_dom_document_relaxng_validate_xml(CVarRef obj, CStrRef source);
-Variant f_dom_node_insert_before(CVarRef obj, CObjRef newnode, CObjRef refnode = null);
+Variant f_dom_node_insert_before(CVarRef obj, CObjRef newnode, CObjRef refnode = uninit_null());
 Variant f_dom_node_replace_child(CVarRef obj, CObjRef newchildobj, CObjRef oldchildobj);
 Variant f_dom_node_remove_child(CVarRef obj, CObjRef node);
 Variant f_dom_node_append_child(CVarRef obj, CObjRef newnode);
@@ -96,7 +96,7 @@ Variant f_dom_text_is_whitespace_in_element_content(CVarRef obj);
 Variant f_dom_xpath_register_ns(CVarRef obj, CStrRef prefix, CStrRef uri);
 Variant f_dom_xpath_query(CVarRef obj, CStrRef expr, CObjRef context = null_object);
 Variant f_dom_xpath_evaluate(CVarRef obj, CStrRef expr, CObjRef context = null_object);
-Variant f_dom_xpath_register_php_functions(CVarRef obj, CVarRef funcs = null);
+Variant f_dom_xpath_register_php_functions(CVarRef obj, CVarRef funcs = uninit_null());
 
 ///////////////////////////////////////////////////////////////////////////////
 // class DOMNode
@@ -115,7 +115,7 @@ class c_DOMNode : public ExtObjectDataFlags<ObjectData::UseGet|ObjectData::UseSe
   public: int64_t t_getlineno();
   public: bool t_hasattributes();
   public: bool t_haschildnodes();
-  public: Variant t_insertbefore(CObjRef newnode, CObjRef refnode = null);
+  public: Variant t_insertbefore(CObjRef newnode, CObjRef refnode = uninit_null());
   public: bool t_isdefaultnamespace(CStrRef namespaceuri);
   public: bool t_issamenode(CObjRef node);
   public: bool t_issupported(CStrRef feature, CStrRef version);
@@ -124,8 +124,8 @@ class c_DOMNode : public ExtObjectDataFlags<ObjectData::UseGet|ObjectData::UseSe
   public: void t_normalize();
   public: Variant t_removechild(CObjRef node);
   public: Variant t_replacechild(CObjRef newchildobj, CObjRef oldchildobj);
-  public: Variant t_c14n(bool exclusive = false, bool with_comments = false, CVarRef xpath = null, CVarRef ns_prefixes = null);
-  public: Variant t_c14nfile(CStrRef uri, bool exclusive = false, bool with_comments = false, CVarRef xpath = null, CVarRef ns_prefixes = null);
+  public: Variant t_c14n(bool exclusive = false, bool with_comments = false, CVarRef xpath = uninit_null(), CVarRef ns_prefixes = uninit_null());
+  public: Variant t_c14nfile(CStrRef uri, bool exclusive = false, bool with_comments = false, CVarRef xpath = uninit_null(), CVarRef ns_prefixes = uninit_null());
   public: Variant t_getnodepath();
   public: Variant t___get(Variant name);
   public: Variant t___set(Variant name, Variant value);
@@ -569,7 +569,7 @@ class c_DOMXPath : public ExtObjectDataFlags<ObjectData::UseGet|ObjectData::UseS
   public: Variant t_evaluate(CStrRef expr, CObjRef context = null_object);
   public: Variant t_query(CStrRef expr, CObjRef context = null_object);
   public: bool t_registernamespace(CStrRef prefix, CStrRef uri);
-  public: Variant t_registerphpfunctions(CVarRef funcs = null);
+  public: Variant t_registerphpfunctions(CVarRef funcs = uninit_null());
   public: Variant t___get(Variant name);
   public: Variant t___set(Variant name, Variant value);
   public: bool t___isset(Variant name);

hphp/runtime/ext/ext_error.h

@@ -31,7 +31,7 @@ void f_debug_print_backtrace();
 String debug_string_backtrace(bool skip);
 Array f_error_get_last();
 bool f_error_log(CStrRef message, int message_type = 0, CStrRef destination = null_string, CStrRef extra_headers = null_string);
-int64_t f_error_reporting(CVarRef level = null);
+int64_t f_error_reporting(CVarRef level = uninit_null());
 bool f_restore_error_handler();
 bool f_restore_exception_handler();
 Variant f_set_error_handler(CVarRef error_handler, int error_types = k_E_ALL);

hphp/runtime/ext/ext_fb.cpp

@@ -267,7 +267,7 @@ int fb_unserialize_from_buffer(Variant &res, const char *buff,
   int type;
   switch (type = buff[(*pos)++]) {
   case T_NULL:
-    res = null;
+    res = uninit_null();
     break;
   case T_BOOLEAN:
     CHECK_ENOUGH(sizeof(int8_t), *pos, buff_len);
@@ -417,7 +417,7 @@ int fb_unserialize_from_buffer(Variant &res, const char *buff,
 Variant f_fb_thrift_serialize(CVarRef thing) {
   int len;
   if (fb_serialized_size(thing, 0, &len)) {
-    return null;
+    return uninit_null();
   }
   String s(len, ReserveString);
   int pos = 0;
@@ -429,7 +429,7 @@ Variant f_fb_thrift_serialize(CVarRef thing) {
 Variant fb_thrift_unserialize(const char* str, int len, VRefParam success,
                               VRefParam errcode /* = null_variant */) {
   int pos = 0;
-  errcode = null;
+  errcode = uninit_null();
   int errcd;
   Variant ret;
   success = false;
@@ -789,7 +789,7 @@ Variant f_fb_compact_serialize(CVarRef thing) {
   // so no need to check for length.
   if (fb_compact_serialize_variant(sd, thing, 0)) {
     DELETE(StringData)(sd);
-    return null;
+    return uninit_null();
   }
 
   return Variant(sd);
@@ -876,7 +876,7 @@ int fb_compact_unserialize_from_buffer(
   code &= kCodeMask;
   switch (code) {
     case FB_CS_NULL:
-      out = null;
+      out = uninit_null();
       break;
 
     case FB_CS_TRUE:
@@ -1002,7 +1002,7 @@ Variant fb_compact_unserialize(const char* str, int len,
     return false;
   }
   success = true;
-  errcode = null;
+  errcode = uninit_null();
   return ret;
 }
 
@@ -1516,7 +1516,7 @@ Array f_fb_call_user_func_array_safe(CVarRef function, CArrRef params) {
   if (f_is_callable(function)) {
     return CREATE_VECTOR2(true, f_call_user_func_array(function, params));
   }
-  return CREATE_VECTOR2(false, null);
+  return CREATE_VECTOR2(false, uninit_null());
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_file.ext_hhvm.cpp

@@ -1283,7 +1283,7 @@ TypedValue * fg1_flock(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   rv->m_data.num = (fh_flock((Value*)(args-0), (int)(args[-1].m_data.num), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
   return rv;
 }
@@ -1295,7 +1295,7 @@ TypedValue* fg_flock(HPHP::VM::ActRec *ar) {
     if (count >= 2LL && count <= 3LL) {
       if ((args-1)->m_type == KindOfInt64 && (args-0)->m_type == KindOfObject) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         rv.m_data.num = (fh_flock((Value*)(args-0), (int)(args[-1].m_data.num), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 3);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_file.h

@@ -32,7 +32,7 @@ namespace HPHP {
 // file handle based file operations
 
 Variant f_fopen(CStrRef filename, CStrRef mode, bool use_include_path = false,
-                CVarRef context = null);
+                CVarRef context = uninit_null());
 Variant f_popen(CStrRef command, CStrRef mode);
 bool f_fclose(CObjRef handle);
 Variant f_pclose(CObjRef handle);
@@ -54,7 +54,7 @@ Variant f_fprintf(int _argc, CObjRef handle, CStrRef format, CArrRef _argv = nul
 Variant f_vfprintf(CObjRef handle, CStrRef format, CArrRef args);
 bool f_fflush(CObjRef handle);
 bool f_ftruncate(CObjRef handle, int64_t size);
-bool f_flock(CObjRef handle, int operation, VRefParam wouldblock = null);
+bool f_flock(CObjRef handle, int operation, VRefParam wouldblock = uninit_null());
 Variant f_fputcsv(CObjRef handle, CArrRef fields, CStrRef delimiter = ",",
                   CStrRef enclosure = "\"");
 Variant f_fgetcsv(CObjRef handle, int64_t length = 0, CStrRef delimiter = ",",
@@ -64,13 +64,13 @@ Variant f_fgetcsv(CObjRef handle, int64_t length = 0, CStrRef delimiter = ",",
 // file name based file operations
 
 Variant f_file_get_contents(CStrRef filename, bool use_include_path = false,
-                            CVarRef context = null, int64_t offset = 0,
+                            CVarRef context = uninit_null(), int64_t offset = 0,
                             int64_t maxlen = 0);
 Variant f_file_put_contents(CStrRef filename, CVarRef data, int flags = 0,
-                            CVarRef context = null);
-Variant f_file(CStrRef filename, int flags = 0, CVarRef context = null);
+                            CVarRef context = uninit_null());
+Variant f_file(CStrRef filename, int flags = 0, CVarRef context = uninit_null());
 Variant f_readfile(CStrRef filename, bool use_include_path = false,
-                   CVarRef context = null);
+                   CVarRef context = uninit_null());
 bool f_move_uploaded_file(CStrRef filename, CStrRef destination);
 Variant f_parse_ini_file(CStrRef filename, bool process_sections = false,
                          int scanner_mode = k_INI_SCANNER_NORMAL);
@@ -92,10 +92,10 @@ bool f_lchown(CStrRef filename, CVarRef user);
 bool f_chgrp(CStrRef filename, CVarRef group);
 bool f_lchgrp(CStrRef filename, CVarRef group);
 bool f_touch(CStrRef filename, int64_t mtime = 0, int64_t atime = 0);
-bool f_copy(CStrRef source, CStrRef dest, CVarRef context = null);
-bool f_rename(CStrRef oldname, CStrRef newname, CVarRef context = null);
+bool f_copy(CStrRef source, CStrRef dest, CVarRef context = uninit_null());
+bool f_rename(CStrRef oldname, CStrRef newname, CVarRef context = uninit_null());
 int64_t f_umask(CVarRef mask = null_variant);
-bool f_unlink(CStrRef filename, CVarRef context = null);
+bool f_unlink(CStrRef filename, CVarRef context = uninit_null());
 bool f_link(CStrRef target, CStrRef link);
 bool f_symlink(CStrRef target, CStrRef link);
 String f_basename(CStrRef path, CStrRef suffix = null_string);
@@ -141,18 +141,18 @@ Variant f_disk_total_space(CStrRef directory);
 // directory functions
 
 bool f_mkdir(CStrRef pathname, int64_t mode = 0777, bool recursive = false,
-             CVarRef context = null);
-bool f_rmdir(CStrRef dirname, CVarRef context = null);
+             CVarRef context = uninit_null());
+bool f_rmdir(CStrRef dirname, CVarRef context = uninit_null());
 String f_dirname(CStrRef path);
 Variant f_getcwd();
 bool f_chdir(CStrRef directory);
 bool f_chroot(CStrRef directory);
 Variant f_dir(CStrRef directory);
-Variant f_opendir(CStrRef path, CVarRef context = null);
+Variant f_opendir(CStrRef path, CVarRef context = uninit_null());
 Variant f_readdir(CObjRef dir_handle);
 void f_rewinddir(CObjRef dir_handle);
 Variant f_scandir(CStrRef directory, bool descending = false,
-                  CVarRef context = null);
+                  CVarRef context = uninit_null());
 void f_closedir(CObjRef dir_handle);
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_function.cpp

@@ -141,14 +141,14 @@ Object f_call_user_func_async(int _argc, CVarRef function,
 
 Variant f_check_user_func_async(CVarRef handles, int timeout /* = -1 */) {
   raise_error("%s is no longer supported", __func__);
-  return null;
+  return uninit_null();
 }
 
 Variant f_end_user_func_async(CObjRef handle,
                               int default_strategy /* = k_GLOBAL_STATE_IGNORE */,
                               CVarRef additional_strategies /* = null */) {
   raise_error("%s is no longer supported", __func__);
-  return null;
+  return uninit_null();
 }
 
 String f_call_user_func_serialized(CStrRef input) {

hphp/runtime/ext/ext_function.ext_hhvm.cpp

@@ -135,7 +135,7 @@ TypedValue * fg1_is_callable(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToBooleanInPlace(args-1);
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   rv->m_data.num = (fh_is_callable((args-0), (count > 1) ? (bool)(args[-1].m_data.num) : (bool)(false), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
   return rv;
 }
@@ -147,7 +147,7 @@ TypedValue* fg_is_callable(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 3LL) {
       if ((count <= 1 || (args-1)->m_type == KindOfBoolean)) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         rv.m_data.num = (fh_is_callable((args-0), (count > 1) ? (bool)(args[-1].m_data.num) : (bool)(false), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 3);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_function.h

@@ -26,12 +26,12 @@ namespace HPHP {
 Array f_get_defined_functions();
 bool f_function_exists(CStrRef function_name, bool autoload = true);
 bool f_is_callable(CVarRef v, bool syntax = false,
-                   VRefParam name = null);
+                   VRefParam name = uninit_null());
 Variant f_call_user_func(int _argc, CVarRef function, CArrRef _argv = null_array);
 Object f_call_user_func_array_async(CVarRef function, CArrRef params);
 Object f_call_user_func_async(int _argc, CVarRef function, CArrRef _argv = null_array);
 Variant f_check_user_func_async(CVarRef handles, int timeout = -1);
-Variant f_end_user_func_async(CObjRef handle, int default_strategy = k_GLOBAL_STATE_IGNORE, CVarRef additional_strategies = null);
+Variant f_end_user_func_async(CObjRef handle, int default_strategy = k_GLOBAL_STATE_IGNORE, CVarRef additional_strategies = uninit_null());
 String f_call_user_func_serialized(CStrRef input);
 Variant f_call_user_func_array_rpc(CStrRef host, int port, CStrRef auth, int timeout, CVarRef function, CArrRef params);
 Variant f_call_user_func_rpc(int _argc, CStrRef host, int port, CStrRef auth, int timeout, CVarRef function, CArrRef _argv = null_array);

hphp/runtime/ext/ext_hash.ext_hhvm.cpp

@@ -485,7 +485,7 @@ TypedValue * fg1_hash_update_file(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  Object defVal2 = null;
+  Object defVal2 = uninit_null();
   rv->m_data.num = (fh_hash_update_file((Value*)(args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2))) ? 1LL : 0LL;
   return rv;
 }
@@ -497,7 +497,7 @@ TypedValue* fg_hash_update_file(HPHP::VM::ActRec *ar) {
     if (count >= 2LL && count <= 3LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfObject) && IS_STRING_TYPE((args-1)->m_type) && (args-0)->m_type == KindOfObject) {
         rv.m_type = KindOfBoolean;
-        Object defVal2 = null;
+        Object defVal2 = uninit_null();
         rv.m_data.num = (fh_hash_update_file((Value*)(args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 3);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_hash.h

@@ -32,7 +32,7 @@ Variant f_hash_file(CStrRef algo, CStrRef filename, bool raw_output = false);
 String f_hash_final(CObjRef context, bool raw_output = false);
 Variant f_hash_hmac_file(CStrRef algo, CStrRef filename, CStrRef key, bool raw_output = false);
 Variant f_hash_hmac(CStrRef algo, CStrRef data, CStrRef key, bool raw_output = false);
-bool f_hash_update_file(CObjRef init_context, CStrRef filename, CObjRef stream_context = null);
+bool f_hash_update_file(CObjRef init_context, CStrRef filename, CObjRef stream_context = uninit_null());
 int64_t f_hash_update_stream(CObjRef context, CObjRef handle, int length = -1);
 bool f_hash_update(CObjRef context, CStrRef data);
 int64_t f_furchash_hphp_ext(CStrRef key, int len, int nPart);

hphp/runtime/ext/ext_hotprofiler.cpp

@@ -1545,7 +1545,7 @@ public:
 
       return ret;
     }
-    return null;
+    return uninit_null();
   }
 
   /**
@@ -1587,7 +1587,7 @@ Variant f_hotprofiler_disable() {
 #ifdef HOTPROFILER
   return s_factory->stop();
 #else
-  return null;
+  return uninit_null();
 #endif
 }
 
@@ -1601,7 +1601,7 @@ Variant f_phprof_disable() {
 #ifdef HOTPROFILER
   return s_factory->stop();
 #else
-  return null;
+  return uninit_null();
 #endif
 }
 
@@ -1661,7 +1661,7 @@ Variant f_xhprof_disable() {
 #ifdef HOTPROFILER
   return s_factory->stop();
 #else
-  return null;
+  return uninit_null();
 #endif
 }
 
@@ -1683,7 +1683,7 @@ Variant f_xhprof_sample_disable() {
 #ifdef HOTPROFILER
   return s_factory->stop();
 #else
-  return null;
+  return uninit_null();
 #endif
 }
 
@@ -1697,7 +1697,7 @@ Variant f_xhprof_run_trace(CStrRef packedTrace, int flags) {
 
   int MHz;
   if (sscanf(syms, xhprof_trace_speed, &MHz) != 1) {
-    return null;
+    return uninit_null();
   }
 
   vector<char *>symbols;
@@ -1720,7 +1720,7 @@ Variant f_xhprof_run_trace(CStrRef packedTrace, int flags) {
       toup->symbol.ptr = NULL;
     } else {
       // corrupt trace
-      return null;
+      return uninit_null();
     }
   }
 
@@ -1731,7 +1731,7 @@ Variant f_xhprof_run_trace(CStrRef packedTrace, int flags) {
   Profiler::extractStats(result, stats, flags, MHz);
   return result;
 #else
-  return null;
+  return uninit_null();
 #endif
 }
 

hphp/runtime/ext/ext_icu.ext_hhvm.cpp

@@ -56,7 +56,7 @@ TypedValue * fg1_icu_match(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count)
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_icu_match((rv), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -68,7 +68,7 @@ TypedValue* fg_icu_match(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 4LL) {
       if ((count <= 3 || (args-3)->m_type == KindOfInt64) && IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_icu_match((&(rv)), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (long)(args[-3].m_data.num) : (long)(0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);

hphp/runtime/ext/ext_icu.h

@@ -31,7 +31,7 @@ namespace HPHP {
 ///////////////////////////////////////////////////////////////////////////////
 
 Variant f_icu_match(CStrRef pattern, CStrRef subject,
-                    VRefParam matches = null, int64_t flags = 0);
+                    VRefParam matches = uninit_null(), int64_t flags = 0);
 String f_icu_transliterate(CStrRef str, bool remove_accents);
 Array f_icu_tokenize(CStrRef text);
 extern const int64_t k_UREGEX_CASE_INSENSITIVE;

hphp/runtime/ext/ext_icu_ucnv.cpp

@@ -106,7 +106,7 @@ Variant c_UConverter::t___destruct() {
     ucnv_close(m_dest);
   }
 
-  return null;
+  return uninit_null();
 }
 
 /* get/set source/dest encodings */
@@ -302,14 +302,14 @@ void c_UConverter::t_setdestinationencoding(CStrRef encoding) {
 
 String c_UConverter::t_getsourceencoding() {
   if (!m_src) {
-    return null;
+    return uninit_null();
   }
 
   UErrorCode error = U_ZERO_ERROR;
   const char *name = ucnv_getName(m_src, &error);
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_getName, error, m_error);
-    return null;
+    return uninit_null();
   }
 
   return String(name);
@@ -317,14 +317,14 @@ String c_UConverter::t_getsourceencoding() {
 
 String c_UConverter::t_getdestinationencoding() {
   if (!m_dest) {
-    return null;
+    return uninit_null();
   }
 
   UErrorCode error = U_ZERO_ERROR;
   const char *name = ucnv_getName(m_dest, &error);
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_getName, error, m_error);
-    return null;
+    return uninit_null();
   }
 
   return String(name);
@@ -374,7 +374,7 @@ String c_UConverter::t_getsubstchars() {
   ucnv_getSubstChars(m_src, chars, &chars_len, &error);
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_getSubstChars, error, m_error);
-    return null;
+    return uninit_null();
   }
 
   return String(chars, chars_len, CopyString);
@@ -391,7 +391,7 @@ Variant c_UConverter::defaultCallback(int64_t reason, VRefParam error) {
       return t_getsubstchars();
   }
 
-  return null;
+  return uninit_null();
 }
 
 Variant c_UConverter::t_fromucallback(int64_t reason,
@@ -422,7 +422,7 @@ String c_UConverter::doConvert(CStrRef str,
   if (!fromCnv || !toCnv) {
     err.code = U_INVALID_STATE_ERROR;
     err.custom_error_message = "Internal converters not initialized";
-    return null;
+    return uninit_null();
   }
 
   /* Convert to UChar pivot encoding */
@@ -430,7 +430,7 @@ String c_UConverter::doConvert(CStrRef str,
                                    str.c_str(), str.size(), &error);
   if (U_FAILURE(error) && error != U_BUFFER_OVERFLOW_ERROR) {
     THROW_UFAILURE(ucnv_toUChars, error, err);
-    return null;
+    return uninit_null();
   }
   // Explicitly include the space for a \u0000 UChar since String
   // only allocates one extra byte (not the 2 needed)
@@ -442,7 +442,7 @@ String c_UConverter::doConvert(CStrRef str,
                            str.c_str(), str.size(), &error);
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_toUChars, error, err);
-    return null;
+    return uninit_null();
   }
   temp[temp_len] = 0;
 
@@ -452,7 +452,7 @@ String c_UConverter::doConvert(CStrRef str,
                                      temp, temp_len, &error);
   if (U_FAILURE(error) && error != U_BUFFER_OVERFLOW_ERROR) {
     THROW_UFAILURE(ucnv_fromUChars, error, err);
-    return null;
+    return uninit_null();
   }
   String destStr(dest_len, ReserveString);
   char *dest = (char*) destStr.mutableSlice().ptr;
@@ -462,7 +462,7 @@ String c_UConverter::doConvert(CStrRef str,
                              temp, temp_len, &error);
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_fromUChars, error, err);
-    return null;
+    return uninit_null();
   }
   return destStr.setSize(dest_len);
 }
@@ -472,20 +472,20 @@ Variant c_UConverter::ti_transcode(const char* cls , CStrRef str,
                                    CArrRef options) {
   UConverter *fromCnv = NULL, *toCnv = NULL;
   if (!setEncoding(fromEncoding, &fromCnv, s_intl_error->m_error)) {
-    return null;
+    return uninit_null();
   }
   if (!setEncoding(toEncoding, &toCnv, s_intl_error->m_error)) {
-    return null;
+    return uninit_null();
   }
   if (options.exists("from_subst") &&
      !setSubstChars(options["from_subst"].toString(), fromCnv,
                                           s_intl_error->m_error)) {
-    return null;
+    return uninit_null();
   }
   if (options.exists("to_subst") &&
      !setSubstChars(options["to_subst"].toString(), toCnv,
                                         s_intl_error->m_error)) {
-    return null;
+    return uninit_null();
   }
   Variant ret = doConvert(str, toCnv, fromCnv, s_intl_error->m_error);
   ucnv_close(toCnv);
@@ -516,7 +516,7 @@ String c_UConverter::ti_reasontext(const char* cls , int64_t reason) {
     UCNV_REASON_CASE(CLONE)
     default:
       raise_warning("Unknown UConverterCallbackReason: %ld", (long)reason);
-      return null;
+      return uninit_null();
   }
 }
 
@@ -537,7 +537,7 @@ Array c_UConverter::ti_getaliases(const char* cls , CStrRef encoding) {
 
   if (U_FAILURE(error)) {
     THROW_UFAILURE(ucnv_getAliases, error, s_intl_error->m_error);
-    return null;
+    return uninit_null();
   }
 
   Array ret = Array::Create();
@@ -546,7 +546,7 @@ Array c_UConverter::ti_getaliases(const char* cls , CStrRef encoding) {
     const char *alias = ucnv_getAlias(encoding, i, &error);
     if (U_FAILURE(error)) {
       THROW_UFAILURE(ucnv_getAlias, error, s_intl_error->m_error);
-      return null;
+      return uninit_null();
     }
     ret.append(alias);
   }
@@ -562,7 +562,7 @@ Array c_UConverter::ti_getstandards(const char* cls ) {
     const char *name = ucnv_getStandard(i, &error);
     if (U_FAILURE(error)) {
       THROW_UFAILURE(ucnv_getStandard, error, s_intl_error->m_error);
-      return null;
+      return uninit_null();
     }
     ret.append(name);
   }

hphp/runtime/ext/ext_icu_uspoof.ext_hhvm.cpp

@@ -87,7 +87,7 @@ TypedValue* tg1_12SpoofChecker_isSuspicious(TypedValue* rv, HPHP::VM::ActRec* ar
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   rv->m_data.num = (th_12SpoofChecker_isSuspicious((this_), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
   return rv;
 }
@@ -101,7 +101,7 @@ TypedValue* tg_12SpoofChecker_isSuspicious(HPHP::VM::ActRec *ar) {
       if (count >= 1LL && count <= 2LL) {
         if (IS_STRING_TYPE((args-0)->m_type)) {
           rv.m_type = KindOfBoolean;
-          VRefParamValue defVal1 = null;
+          VRefParamValue defVal1 = uninit_null();
           rv.m_data.num = (th_12SpoofChecker_isSuspicious((this_), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
           frame_free_locals_inl(ar, 2);
           memcpy(&ar->m_r, &rv, sizeof(TypedValue));
@@ -154,7 +154,7 @@ TypedValue* tg1_12SpoofChecker_areConfusable(TypedValue* rv, HPHP::VM::ActRec* a
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   rv->m_data.num = (th_12SpoofChecker_areConfusable((this_), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
   return rv;
 }
@@ -168,7 +168,7 @@ TypedValue* tg_12SpoofChecker_areConfusable(HPHP::VM::ActRec *ar) {
       if (count >= 2LL && count <= 3LL) {
         if (IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
           rv.m_type = KindOfBoolean;
-          VRefParamValue defVal2 = null;
+          VRefParamValue defVal2 = uninit_null();
           rv.m_data.num = (th_12SpoofChecker_areConfusable((this_), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
           frame_free_locals_inl(ar, 3);
           memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_icu_uspoof.h

@@ -52,8 +52,8 @@ class c_SpoofChecker : public ExtObjectData {
   public: c_SpoofChecker(VM::Class* cls = c_SpoofChecker::s_cls);
   public: ~c_SpoofChecker();
   public: void t___construct();
-  public: bool t_issuspicious(CStrRef text, VRefParam issuesFound = null);
-  public: bool t_areconfusable(CStrRef s1, CStrRef s2, VRefParam issuesFound = null);
+  public: bool t_issuspicious(CStrRef text, VRefParam issuesFound = uninit_null());
+  public: bool t_areconfusable(CStrRef s1, CStrRef s2, VRefParam issuesFound = uninit_null());
   public: void t_setallowedlocales(CStrRef localesList);
   public: void t_setchecks(int checks);
 

hphp/runtime/ext/ext_image.cpp

@@ -1578,7 +1578,7 @@ Variant f_getimagesize(CStrRef filename, VRefParam imageinfo /* = null */) {
   int itype = 0;
   struct gfxinfo *result = NULL;
   if (imageinfo.isReferenced()) {
-    imageinfo = null;
+    imageinfo = uninit_null();
   }
 
   Array ret;
@@ -7602,7 +7602,7 @@ static void add_assoc_image_info(Array &value, bool sub_array,
         name = uname;
       }
       if (info_data->length==0) {
-        tmpi->set(String(name, CopyString), null);
+        tmpi->set(String(name, CopyString), uninit_null());
       } else {
         switch (info_data->format) {
         default:

hphp/runtime/ext/ext_image.ext_hhvm.cpp

@@ -74,7 +74,7 @@ TypedValue * fg1_getimagesize(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t coun
 TypedValue * fg1_getimagesize(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   fh_getimagesize((rv), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -86,7 +86,7 @@ TypedValue* fg_getimagesize(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 2LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         fh_getimagesize((&(rv)), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 2);
@@ -3556,7 +3556,7 @@ TypedValue * fg1_imageftbbox(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count
   if ((args-0)->m_type != KindOfDouble) {
     tvCastToDoubleInPlace(args-0);
   }
-  Array defVal4 = null;
+  Array defVal4 = uninit_null();
   fh_imageftbbox((rv), (args[-0].m_data.dbl), (args[-1].m_data.dbl), (Value*)(args-2), (Value*)(args-3), (count > 4) ? (Value*)(args-4) : (Value*)(&defVal4));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -3568,7 +3568,7 @@ TypedValue* fg_imageftbbox(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 4LL && count <= 5LL) {
       if ((count <= 4 || (args-4)->m_type == KindOfArray) && IS_STRING_TYPE((args-3)->m_type) && IS_STRING_TYPE((args-2)->m_type) && (args-1)->m_type == KindOfDouble && (args-0)->m_type == KindOfDouble) {
-        Array defVal4 = null;
+        Array defVal4 = uninit_null();
         fh_imageftbbox((&(rv)), (args[-0].m_data.dbl), (args[-1].m_data.dbl), (Value*)(args-2), (Value*)(args-3), (count > 4) ? (Value*)(args-4) : (Value*)(&defVal4));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 5);
@@ -3647,7 +3647,7 @@ TypedValue * fg1_imagefttext(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  Array defVal8 = null;
+  Array defVal8 = uninit_null();
   fh_imagefttext((rv), (Value*)(args-0), (args[-1].m_data.dbl), (args[-2].m_data.dbl), (int)(args[-3].m_data.num), (int)(args[-4].m_data.num), (int)(args[-5].m_data.num), (Value*)(args-6), (Value*)(args-7), (count > 8) ? (Value*)(args-8) : (Value*)(&defVal8));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -3659,7 +3659,7 @@ TypedValue* fg_imagefttext(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 8LL && count <= 9LL) {
       if ((count <= 8 || (args-8)->m_type == KindOfArray) && IS_STRING_TYPE((args-7)->m_type) && IS_STRING_TYPE((args-6)->m_type) && (args-5)->m_type == KindOfInt64 && (args-4)->m_type == KindOfInt64 && (args-3)->m_type == KindOfInt64 && (args-2)->m_type == KindOfDouble && (args-1)->m_type == KindOfDouble && (args-0)->m_type == KindOfObject) {
-        Array defVal8 = null;
+        Array defVal8 = uninit_null();
         fh_imagefttext((&(rv)), (Value*)(args-0), (args[-1].m_data.dbl), (args[-2].m_data.dbl), (int)(args[-3].m_data.num), (int)(args[-4].m_data.num), (int)(args[-5].m_data.num), (Value*)(args-6), (Value*)(args-7), (count > 8) ? (Value*)(args-8) : (Value*)(&defVal8));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 9);
@@ -6615,9 +6615,9 @@ TypedValue * fg1_exif_thumbnail(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t co
 TypedValue * fg1_exif_thumbnail(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
-  VRefParamValue defVal2 = null;
-  VRefParamValue defVal3 = null;
+  VRefParamValue defVal1 = uninit_null();
+  VRefParamValue defVal2 = uninit_null();
+  VRefParamValue defVal3 = uninit_null();
   fh_exif_thumbnail((rv), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -6629,9 +6629,9 @@ TypedValue* fg_exif_thumbnail(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal1 = null;
-        VRefParamValue defVal2 = null;
-        VRefParamValue defVal3 = null;
+        VRefParamValue defVal1 = uninit_null();
+        VRefParamValue defVal2 = uninit_null();
+        VRefParamValue defVal3 = uninit_null();
         fh_exif_thumbnail((&(rv)), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);

hphp/runtime/ext/ext_image.h

@@ -50,7 +50,7 @@ private:
 };
 
 Array f_gd_info();
-Variant f_getimagesize(CStrRef filename, VRefParam imageinfo = null);
+Variant f_getimagesize(CStrRef filename, VRefParam imageinfo = uninit_null());
 String f_image_type_to_extension(int imagetype, bool include_dot = true);
 String f_image_type_to_mime_type(int imagetype);
 bool f_image2wbmp(CObjRef image, CStrRef filename = null_string, int threshold = -1);
@@ -105,8 +105,8 @@ bool f_imagefilltoborder(CObjRef image, int x, int y, int border, int color);
 bool f_imagefilter(CObjRef image, int filtertype, int arg1 = 0, int arg2 = 0, int arg3 = 0, int arg4 = 0);
 int64_t f_imagefontheight(int font);
 int64_t f_imagefontwidth(int font);
-Variant f_imageftbbox(double size, double angle, CStrRef font_file, CStrRef text, CArrRef extrainfo = null);
-Variant f_imagefttext(CObjRef image, double size, double angle, int x, int y, int col, CStrRef font_file, CStrRef text, CArrRef extrainfo = null);
+Variant f_imageftbbox(double size, double angle, CStrRef font_file, CStrRef text, CArrRef extrainfo = uninit_null());
+Variant f_imagefttext(CObjRef image, double size, double angle, int x, int y, int col, CStrRef font_file, CStrRef text, CArrRef extrainfo = uninit_null());
 bool f_imagegammacorrect(CObjRef image, double inputgamma, double outputgamma);
 bool f_imagegd2(CObjRef image, CStrRef filename = null_string, int chunk_size = 0, int type = 0);
 bool f_imagegd(CObjRef image, CStrRef filename = null_string);
@@ -155,7 +155,7 @@ Variant f_exif_imagetype(CStrRef filename);
 Variant f_exif_read_data(CStrRef filename, CStrRef sections = null_string, bool arrays = false, bool thumbnail = false);
 Variant f_read_exif_data(CStrRef filename, CStrRef sections = null_string, bool arrays = false, bool thumbnail = false);
 Variant f_exif_tagname(int index);
-Variant f_exif_thumbnail(CStrRef filename, VRefParam width = null, VRefParam height = null, VRefParam imagetype = null);
+Variant f_exif_thumbnail(CStrRef filename, VRefParam width = uninit_null(), VRefParam height = uninit_null(), VRefParam imagetype = uninit_null());
 
 ///////////////////////////////////////////////////////////////////////////////
 }

hphp/runtime/ext/ext_imagesprite.cpp

@@ -510,7 +510,7 @@ Object c_ImageSprite::t_addurl(CStrRef url, int timeout_ms /* = 0 */,
 }
 
 Object c_ImageSprite::t_clear(CVarRef files /* = null */) {
-  if (same(files, null)) {
+  if (same(files, uninit_null())) {
     // Clear them all, might as well __destruct
     t___destruct();
   } else if (files.isArray()) {
@@ -1176,7 +1176,7 @@ Variant c_ImageSprite::t___destruct() {
   m_img_errors = Array::Create();
   m_sprite_errors = Array::Create();
 
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_imagesprite.ext_hhvm.cpp

@@ -98,7 +98,7 @@ TypedValue* tg1_11ImageSprite_addFile(TypedValue* rv, HPHP::VM::ActRec* ar, int6
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  Array defVal1 = null;
+  Array defVal1 = uninit_null();
   th_11ImageSprite_addFile((Value*)(rv), (this_), (Value*)(args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1));
   if (rv->m_data.num == 0LL)rv->m_type = KindOfNull;
   return rv;
@@ -113,7 +113,7 @@ TypedValue* tg_11ImageSprite_addFile(HPHP::VM::ActRec *ar) {
       if (count >= 1LL && count <= 2LL) {
         if ((count <= 1 || (args-1)->m_type == KindOfArray) && IS_STRING_TYPE((args-0)->m_type)) {
           rv.m_type = KindOfObject;
-          Array defVal1 = null;
+          Array defVal1 = uninit_null();
           th_11ImageSprite_addFile((Value*)(&(rv)), (this_), (Value*)(args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1));
           if (rv.m_data.num == 0LL) rv.m_type = KindOfNull;
           frame_free_locals_inl(ar, 2);
@@ -171,7 +171,7 @@ TypedValue* tg1_11ImageSprite_addString(TypedValue* rv, HPHP::VM::ActRec* ar, in
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  Array defVal2 = null;
+  Array defVal2 = uninit_null();
   th_11ImageSprite_addString((Value*)(rv), (this_), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
   if (rv->m_data.num == 0LL)rv->m_type = KindOfNull;
   return rv;
@@ -186,7 +186,7 @@ TypedValue* tg_11ImageSprite_addString(HPHP::VM::ActRec *ar) {
       if (count >= 2LL && count <= 3LL) {
         if ((count <= 2 || (args-2)->m_type == KindOfArray) && IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
           rv.m_type = KindOfObject;
-          Array defVal2 = null;
+          Array defVal2 = uninit_null();
           th_11ImageSprite_addString((Value*)(&(rv)), (this_), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
           if (rv.m_data.num == 0LL) rv.m_type = KindOfNull;
           frame_free_locals_inl(ar, 3);
@@ -245,7 +245,7 @@ TypedValue* tg1_11ImageSprite_addUrl(TypedValue* rv, HPHP::VM::ActRec* ar, int64
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  Array defVal2 = null;
+  Array defVal2 = uninit_null();
   th_11ImageSprite_addUrl((Value*)(rv), (this_), (Value*)(args-0), (count > 1) ? (int)(args[-1].m_data.num) : (int)(0), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
   if (rv->m_data.num == 0LL)rv->m_type = KindOfNull;
   return rv;
@@ -260,7 +260,7 @@ TypedValue* tg_11ImageSprite_addUrl(HPHP::VM::ActRec *ar) {
       if (count >= 1LL && count <= 3LL) {
         if ((count <= 2 || (args-2)->m_type == KindOfArray) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
           rv.m_type = KindOfObject;
-          Array defVal2 = null;
+          Array defVal2 = uninit_null();
           th_11ImageSprite_addUrl((Value*)(&(rv)), (this_), (Value*)(args-0), (count > 1) ? (int)(args[-1].m_data.num) : (int)(0), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
           if (rv.m_data.num == 0LL) rv.m_type = KindOfNull;
           frame_free_locals_inl(ar, 3);

hphp/runtime/ext/ext_imagesprite.h

@@ -40,10 +40,10 @@ class c_ImageSprite : public ExtObjectData, public Sweepable {
   public: c_ImageSprite(VM::Class* cls = c_ImageSprite::s_cls);
   public: ~c_ImageSprite();
   public: void t___construct();
-  public: Object t_addfile(CStrRef file, CArrRef options = null);
-  public: Object t_addstring(CStrRef id, CStrRef data, CArrRef options = null);
-  public: Object t_addurl(CStrRef url, int timeout_ms = 0, CArrRef Options = null);
-  public: Object t_clear(CVarRef paths = null);
+  public: Object t_addfile(CStrRef file, CArrRef options = uninit_null());
+  public: Object t_addstring(CStrRef id, CStrRef data, CArrRef options = uninit_null());
+  public: Object t_addurl(CStrRef url, int timeout_ms = 0, CArrRef Options = uninit_null());
+  public: Object t_clear(CVarRef paths = uninit_null());
   public: Object t_loaddims(bool block = false);
   public: Object t_loadimages(bool block = false);
   public: String t_output(CStrRef output_file = null_string, CStrRef format = "png", int quality = 75);

hphp/runtime/ext/ext_imap.cpp

@@ -1221,7 +1221,7 @@ Variant f_imap_last_error() {
       return String((const char *)cur->text.data, CopyString);
     }
   }
-  return null;
+  return uninit_null();
 }
 
 Variant f_imap_list(CObjRef imap_stream, CStrRef ref, CStrRef pattern) {

hphp/runtime/ext/ext_intl.cpp

@@ -588,7 +588,7 @@ Variant c_Normalizer::ti_isnormalized(const char* cls , CStrRef input,
     s_intl_error->m_error.code = U_ILLEGAL_ARGUMENT_ERROR;
     s_intl_error->m_error.custom_error_message =
       "normalizer_isnormalized: illegal normalization form";
-    return null;
+    return uninit_null();
   }
 
   /* First convert the string to UTF-16. */
@@ -639,7 +639,7 @@ Variant c_Normalizer::ti_normalize(const char* cls , CStrRef input,
     s_intl_error->m_error.code = U_ILLEGAL_ARGUMENT_ERROR;
     s_intl_error->m_error.custom_error_message =
       "normalizer_normalize: illegal normalization form";
-    return null;
+    return uninit_null();
   }
 
   /* First convert the string to UTF-16. */
@@ -653,7 +653,7 @@ Variant c_Normalizer::ti_normalize(const char* cls , CStrRef input,
     s_intl_error->m_error.custom_error_message =
         "Error converting string to UTF-16.";
     free(uinput);
-    return null;
+    return uninit_null();
   }
 
   /* Allocate memory for the destination buffer for normalization */
@@ -675,7 +675,7 @@ Variant c_Normalizer::ti_normalize(const char* cls , CStrRef input,
       status != U_STRING_NOT_TERMINATED_WARNING) {
     free(uret_buf);
     free(uinput);
-    return null;
+    return uninit_null();
   }
 
   if (size_needed > uret_len) {
@@ -699,7 +699,7 @@ Variant c_Normalizer::ti_normalize(const char* cls , CStrRef input,
       s_intl_error->m_error.custom_error_message = "Error normalizing string";
       free(uret_buf);
       free(uinput);
-      return null;
+      return uninit_null();
     }
   }
 
@@ -716,7 +716,7 @@ Variant c_Normalizer::ti_normalize(const char* cls , CStrRef input,
     s_intl_error->m_error.code = status;
     s_intl_error->m_error.custom_error_message =
       "normalizer_normalize: error converting normalized text UTF-8";
-    return null;
+    return uninit_null();
   }
 
   return String(ret_buf, ret_len, AttachString);

hphp/runtime/ext/ext_intl.ext_hhvm.cpp

@@ -782,7 +782,7 @@ TypedValue * fg1_idn_to_ascii(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t coun
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal3 = null;
+  VRefParamValue defVal3 = uninit_null();
   fh_idn_to_ascii((rv), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -794,7 +794,7 @@ TypedValue* fg_idn_to_ascii(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfInt64) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal3 = null;
+        VRefParamValue defVal3 = uninit_null();
         fh_idn_to_ascii((&(rv)), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);
@@ -852,7 +852,7 @@ TypedValue * fg1_idn_to_unicode(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t co
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal3 = null;
+  VRefParamValue defVal3 = uninit_null();
   fh_idn_to_unicode((rv), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -864,7 +864,7 @@ TypedValue* fg_idn_to_unicode(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfInt64) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal3 = null;
+        VRefParamValue defVal3 = uninit_null();
         fh_idn_to_unicode((&(rv)), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);
@@ -922,7 +922,7 @@ TypedValue * fg1_idn_to_utf8(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal3 = null;
+  VRefParamValue defVal3 = uninit_null();
   fh_idn_to_utf8((rv), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -934,7 +934,7 @@ TypedValue* fg_idn_to_utf8(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfInt64) && (count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal3 = null;
+        VRefParamValue defVal3 = uninit_null();
         fh_idn_to_utf8((&(rv)), (Value*)(args-0), (count > 1) ? (long)(args[-1].m_data.num) : (long)(0), (count > 2) ? (long)(args[-2].m_data.num) : (long)(0), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);

hphp/runtime/ext/ext_intl.h

@@ -45,9 +45,9 @@ Variant f_collator_set_attribute(CVarRef obj, int64_t attr, int64_t val);
 Variant f_collator_set_strength(CVarRef obj, int64_t strength);
 Variant f_collator_sort_with_sort_keys(CVarRef obj, VRefParam arr);
 Variant f_collator_sort(CVarRef obj, VRefParam arr, int64_t sort_flag = q_Collator$$SORT_REGULAR);
-Variant f_idn_to_ascii(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = null);
-Variant f_idn_to_unicode(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = null);
-Variant f_idn_to_utf8(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = null);
+Variant f_idn_to_ascii(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = uninit_null());
+Variant f_idn_to_unicode(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = uninit_null());
+Variant f_idn_to_utf8(CStrRef domain, int64_t options = 0, int64_t variant = 0, VRefParam idna_info = uninit_null());
 extern const int64_t q_Collator$$SORT_REGULAR;
 extern const int64_t q_Collator$$SORT_NUMERIC;
 extern const int64_t q_Collator$$SORT_STRING;

hphp/runtime/ext/ext_ipc.ext_hhvm.cpp

@@ -227,7 +227,7 @@ TypedValue * fg1_msg_send(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  VRefParamValue defVal5 = null;
+  VRefParamValue defVal5 = uninit_null();
   rv->m_data.num = (fh_msg_send((Value*)(args-0), (long)(args[-1].m_data.num), (args-2), (count > 3) ? (bool)(args[-3].m_data.num) : (bool)(true), (count > 4) ? (bool)(args[-4].m_data.num) : (bool)(true), (count > 5) ? (args-5) : (TypedValue*)(&defVal5))) ? 1LL : 0LL;
   return rv;
 }
@@ -239,7 +239,7 @@ TypedValue* fg_msg_send(HPHP::VM::ActRec *ar) {
     if (count >= 3LL && count <= 6LL) {
       if ((count <= 4 || (args-4)->m_type == KindOfBoolean) && (count <= 3 || (args-3)->m_type == KindOfBoolean) && (args-1)->m_type == KindOfInt64 && (args-0)->m_type == KindOfObject) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal5 = null;
+        VRefParamValue defVal5 = uninit_null();
         rv.m_data.num = (fh_msg_send((Value*)(args-0), (long)(args[-1].m_data.num), (args-2), (count > 3) ? (bool)(args[-3].m_data.num) : (bool)(true), (count > 4) ? (bool)(args[-4].m_data.num) : (bool)(true), (count > 5) ? (args-5) : (TypedValue*)(&defVal5))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 6);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));
@@ -306,7 +306,7 @@ TypedValue * fg1_msg_receive(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  VRefParamValue defVal7 = null;
+  VRefParamValue defVal7 = uninit_null();
   rv->m_data.num = (fh_msg_receive((Value*)(args-0), (long)(args[-1].m_data.num), (args-2), (long)(args[-3].m_data.num), (args-4), (count > 5) ? (bool)(args[-5].m_data.num) : (bool)(true), (count > 6) ? (long)(args[-6].m_data.num) : (long)(0), (count > 7) ? (args-7) : (TypedValue*)(&defVal7))) ? 1LL : 0LL;
   return rv;
 }
@@ -318,7 +318,7 @@ TypedValue* fg_msg_receive(HPHP::VM::ActRec *ar) {
     if (count >= 5LL && count <= 8LL) {
       if ((count <= 6 || (args-6)->m_type == KindOfInt64) && (count <= 5 || (args-5)->m_type == KindOfBoolean) && (args-3)->m_type == KindOfInt64 && (args-1)->m_type == KindOfInt64 && (args-0)->m_type == KindOfObject) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal7 = null;
+        VRefParamValue defVal7 = uninit_null();
         rv.m_data.num = (fh_msg_receive((Value*)(args-0), (long)(args[-1].m_data.num), (args-2), (long)(args[-3].m_data.num), (args-4), (count > 5) ? (bool)(args[-5].m_data.num) : (bool)(true), (count > 6) ? (long)(args[-6].m_data.num) : (long)(0), (count > 7) ? (args-7) : (TypedValue*)(&defVal7))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 8);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_ipc.h

@@ -30,10 +30,10 @@ Variant f_msg_get_queue(int64_t key, int64_t perms = 0666);
 bool f_msg_queue_exists(int64_t key);
 bool f_msg_send(CObjRef queue, int64_t msgtype, CVarRef message,
                 bool serialize = true, bool blocking = true,
-                VRefParam errorcode = null);
+                VRefParam errorcode = uninit_null());
 bool f_msg_receive(CObjRef queue, int64_t desiredmsgtype, VRefParam msgtype,
                    int64_t maxsize, VRefParam message, bool unserialize = true,
-                   int64_t flags = 0, VRefParam errorcode = null);
+                   int64_t flags = 0, VRefParam errorcode = uninit_null());
 bool f_msg_remove_queue(CObjRef queue);
 bool f_msg_set_queue(CObjRef queue, CArrRef data);
 Array f_msg_stat_queue(CObjRef queue);

hphp/runtime/ext/ext_iterator.cpp

@@ -501,20 +501,20 @@ void c_MutableArrayIterator::t___construct(VRefParam array) {
 }
 
 Variant c_MutableArrayIterator::t___destruct() {
-  return null;
+  return uninit_null();
 }
 
 Variant c_MutableArrayIterator::t_currentref() {
-  if (!m_valid) return null;
+  if (!m_valid) return uninit_null();
   MArrayIter& mi = marr();
-  if (mi.end()) return null;
+  if (mi.end()) return uninit_null();
   return strongBind(mi.val());
 }
 
 Variant c_MutableArrayIterator::t_current() {
-  if (!m_valid) return null;
+  if (!m_valid) return uninit_null();
   MArrayIter& mi = marr();
-  if (mi.end()) return null;
+  if (mi.end()) return uninit_null();
   return mi.val();
 }
 

hphp/runtime/ext/ext_json.cpp

@@ -51,7 +51,7 @@ String f_json_encode(CVarRef value, CVarRef options /* = 0 */) {
 Variant f_json_decode(CStrRef json, bool assoc /* = false */,
                       CVarRef options /* = 0 */) {
   if (json.empty()) {
-    return null;
+    return uninit_null();
   }
 
   int64_t json_options = options.toInt64();
@@ -66,7 +66,7 @@ Variant f_json_decode(CStrRef json, bool assoc /* = false */,
   }
 
   if (json.size() == 4) {
-    if (!strcasecmp(json.data(), "null")) return null;
+    if (!strcasecmp(json.data(), "null")) return uninit_null();
     if (!strcasecmp(json.data(), "true")) return true;
   } else if (json.size() == 5 && !strcasecmp(json.data(), "false")) {
     return false;
@@ -92,7 +92,7 @@ Variant f_json_decode(CStrRef json, bool assoc /* = false */,
   }
 
   if (ch0 == '{' || ch0 == '[') { /* invalid JSON string */
-    return null;
+    return uninit_null();
   }
 
   return json;

hphp/runtime/ext/ext_ldap.cpp

@@ -1012,7 +1012,7 @@ Variant f_ldap_get_entries(CObjRef link, CObjRef result) {
   Array ret;
   ret.set("count", num_entries);
   if (num_entries == 0) {
-    return null;
+    return uninit_null();
   }
 
   LDAPMessage *ldap_result_entry = ldap_first_entry(ldap, res->data);

hphp/runtime/ext/ext_ldap.ext_hhvm.cpp

@@ -2143,9 +2143,9 @@ TypedValue * fg1_ldap_parse_result(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t
   if ((args-0)->m_type != KindOfObject) {
     tvCastToObjectInPlace(args-0);
   }
-  VRefParamValue defVal3 = null;
-  VRefParamValue defVal4 = null;
-  VRefParamValue defVal5 = null;
+  VRefParamValue defVal3 = uninit_null();
+  VRefParamValue defVal4 = uninit_null();
+  VRefParamValue defVal5 = uninit_null();
   rv->m_data.num = (fh_ldap_parse_result((Value*)(args-0), (Value*)(args-1), (args-2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3), (count > 4) ? (args-4) : (TypedValue*)(&defVal4), (count > 5) ? (args-5) : (TypedValue*)(&defVal5))) ? 1LL : 0LL;
   return rv;
 }
@@ -2157,9 +2157,9 @@ TypedValue* fg_ldap_parse_result(HPHP::VM::ActRec *ar) {
     if (count >= 3LL && count <= 6LL) {
       if ((args-1)->m_type == KindOfObject && (args-0)->m_type == KindOfObject) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal3 = null;
-        VRefParamValue defVal4 = null;
-        VRefParamValue defVal5 = null;
+        VRefParamValue defVal3 = uninit_null();
+        VRefParamValue defVal4 = uninit_null();
+        VRefParamValue defVal5 = uninit_null();
         rv.m_data.num = (fh_ldap_parse_result((Value*)(args-0), (Value*)(args-1), (args-2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3), (count > 4) ? (args-4) : (TypedValue*)(&defVal4), (count > 5) ? (args-5) : (TypedValue*)(&defVal5))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 6);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_ldap.h

@@ -61,7 +61,7 @@ Variant f_ldap_next_attribute(CObjRef link, CObjRef result_entry);
 Variant f_ldap_first_reference(CObjRef link, CObjRef result);
 Variant f_ldap_next_reference(CObjRef link, CObjRef result_entry);
 bool f_ldap_parse_reference(CObjRef link, CObjRef result_entry, VRefParam referrals);
-bool f_ldap_parse_result(CObjRef link, CObjRef result, VRefParam errcode, VRefParam matcheddn = null, VRefParam errmsg = null, VRefParam referrals = null);
+bool f_ldap_parse_result(CObjRef link, CObjRef result, VRefParam errcode, VRefParam matcheddn = uninit_null(), VRefParam errmsg = uninit_null(), VRefParam referrals = uninit_null());
 bool f_ldap_free_result(CObjRef result);
 Variant f_ldap_get_values_len(CObjRef link, CObjRef result_entry, CStrRef attribute);
 Variant f_ldap_get_values(CObjRef link, CObjRef result_entry, CStrRef attribute);

hphp/runtime/ext/ext_mb.ext_hhvm.cpp

@@ -1342,7 +1342,7 @@ TypedValue * fg1_mb_ereg(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) __
 TypedValue * fg1_mb_ereg(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToStringInPlace(args-1);
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_mb_ereg((rv), (args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -1354,7 +1354,7 @@ TypedValue* fg_mb_ereg(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-1)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_mb_ereg((&(rv)), (args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -1462,7 +1462,7 @@ TypedValue * fg1_mb_eregi(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) _
 TypedValue * fg1_mb_eregi(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToStringInPlace(args-1);
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_mb_eregi((rv), (args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -1474,7 +1474,7 @@ TypedValue* fg_mb_eregi(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-1)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_mb_eregi((&(rv)), (args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -1823,7 +1823,7 @@ TypedValue * fg1_mb_parse_str(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t coun
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   rv->m_data.num = (fh_mb_parse_str((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
   return rv;
 }
@@ -1835,7 +1835,7 @@ TypedValue* fg_mb_parse_str(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 2LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         rv.m_data.num = (fh_mb_parse_str((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 2);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_mb.h

@@ -48,16 +48,16 @@ Variant f_mb_ereg_search_pos(CStrRef pattern = null_string, CStrRef option = nul
 Variant f_mb_ereg_search_regs(CStrRef pattern = null_string, CStrRef option = null_string);
 bool f_mb_ereg_search_setpos(int position);
 Variant f_mb_ereg_search(CStrRef pattern = null_string, CStrRef option = null_string);
-Variant f_mb_ereg(CVarRef pattern, CStrRef str, VRefParam regs = null);
+Variant f_mb_ereg(CVarRef pattern, CStrRef str, VRefParam regs = uninit_null());
 Variant f_mb_eregi_replace(CVarRef pattern, CStrRef replacement, CStrRef str, CStrRef option = null_string);
-Variant f_mb_eregi(CVarRef pattern, CStrRef str, VRefParam regs = null);
+Variant f_mb_eregi(CVarRef pattern, CStrRef str, VRefParam regs = uninit_null());
 Variant f_mb_get_info(CStrRef type = null_string);
 Variant f_mb_http_input(CStrRef type = null_string);
 Variant f_mb_http_output(CStrRef encoding = null_string);
 Variant f_mb_internal_encoding(CStrRef encoding = null_string);
 Variant f_mb_language(CStrRef language = null_string);
 String f_mb_output_handler(CStrRef contents, int status);
-bool f_mb_parse_str(CStrRef encoded_string, VRefParam result = null);
+bool f_mb_parse_str(CStrRef encoded_string, VRefParam result = uninit_null());
 Variant f_mb_preferred_mime_name(CStrRef encoding);
 Variant f_mb_regex_encoding(CStrRef encoding = null_string);
 String f_mb_regex_set_options(CStrRef options = null_string);

hphp/runtime/ext/ext_memcache.cpp

@@ -144,11 +144,11 @@ String static memcache_prepare_for_storage(CVarRef var, int &flag) {
 Variant static memcache_fetch_from_storage(const char *payload,
                                            size_t payload_len,
                                            uint32_t flags) {
-  Variant ret = null;
+  Variant ret = uninit_null();
 
   if (flags & MMC_COMPRESSED) {
     raise_warning("Unable to handle compressed values yet");
-    return null;
+    return uninit_null();
   }
 
   if (flags & MMC_SERIALIZED) {
@@ -547,7 +547,7 @@ bool c_Memcache::t_addserver(CStrRef host, int port /* = 11211 */,
 
 Variant c_Memcache::t___destruct() {
   t_close();
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_memcache.ext_hhvm.cpp

@@ -397,7 +397,7 @@ TypedValue * fg1_memcache_get(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t coun
 TypedValue * fg1_memcache_get(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToObjectInPlace(args-0);
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_memcache_get((rv), (Value*)(args-0), (args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -409,7 +409,7 @@ TypedValue* fg_memcache_get(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if ((args-0)->m_type == KindOfObject) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_memcache_get((&(rv)), (Value*)(args-0), (args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -1764,7 +1764,7 @@ TypedValue* tg_8Memcache_get(HPHP::VM::ActRec *ar) {
     ObjectData* this_ = (ar->hasThis() ? ar->getThis() : NULL);
     if (this_) {
       if (count >= 1LL && count <= 2LL) {
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         th_8Memcache_get((&(rv)), (this_), (args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_inl(ar, 2);

hphp/runtime/ext/ext_memcache.h

@@ -30,7 +30,7 @@ Object f_memcache_pconnect(CStrRef host, int port = 0, int timeout = 0, int time
 bool f_memcache_add(CObjRef memcache, CStrRef key, CVarRef var, int flag = 0, int expire = 0);
 bool f_memcache_set(CObjRef memcache, CStrRef key, CVarRef var, int flag = 0, int expire = 0);
 bool f_memcache_replace(CObjRef memcache, CStrRef key, CVarRef var, int flag = 0, int expire = 0);
-Variant f_memcache_get(CObjRef memcache, CVarRef key, VRefParam flags = null);
+Variant f_memcache_get(CObjRef memcache, CVarRef key, VRefParam flags = uninit_null());
 bool f_memcache_delete(CObjRef memcache, CStrRef key, int expire = 0);
 int64_t f_memcache_increment(CObjRef memcache, CStrRef key, int offset = 1);
 int64_t f_memcache_decrement(CObjRef memcache, CStrRef key, int offset = 1);
@@ -63,7 +63,7 @@ class c_Memcache : public ExtObjectData, public Sweepable {
   public: bool t_add(CStrRef key, CVarRef var, int flag = 0, int expire = 0);
   public: bool t_set(CStrRef key, CVarRef var, int flag = 0, int expire = 0);
   public: bool t_replace(CStrRef key, CVarRef var, int flag = 0, int expire = 0);
-  public: Variant t_get(CVarRef key, VRefParam flags = null);
+  public: Variant t_get(CVarRef key, VRefParam flags = uninit_null());
   public: bool t_delete(CStrRef key, int expire = 0);
   public: int64_t t_increment(CStrRef key, int offset = 1);
   public: int64_t t_decrement(CStrRef key, int offset = 1);

hphp/runtime/ext/ext_misc.cpp

@@ -55,7 +55,7 @@ int64_t f_connection_timeout() {
 }
 
 Variant f_constant(CStrRef name) {
-  if (!name.get()) return null;
+  if (!name.get()) return uninit_null();
   const char *data = name.data();
   int len = name.length();
   char *colon;
@@ -91,7 +91,7 @@ Variant f_constant(CStrRef name) {
       }
     }
     raise_warning("Couldn't find constant %s", data);
-    return null;
+    return uninit_null();
   } else {
     TypedValue* cns = g_vmContext->getCns(name.get());
     if (cns == NULL) {
@@ -100,7 +100,7 @@ Variant f_constant(CStrRef name) {
       }
     }
     if (cns) return tvAsVariant(cns);
-    return null;
+    return uninit_null();
   }
 }
 

hphp/runtime/ext/ext_misc.ext_hhvm.cpp

@@ -829,7 +829,7 @@ TypedValue * fg1_php_check_syntax(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   rv->m_data.num = (fh_php_check_syntax((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
   return rv;
 }
@@ -841,7 +841,7 @@ TypedValue* fg_php_check_syntax(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 2LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         rv.m_data.num = (fh_php_check_syntax((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 2);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_misc.h

@@ -41,7 +41,7 @@ Variant f_show_source(CStrRef filename, bool ret = false);
 Variant f_highlight_string(CStrRef str, bool ret = false);
 int64_t f_ignore_user_abort(bool setting = false);
 Variant f_pack(int _argc, CStrRef format, CArrRef _argv = null_array);
-bool f_php_check_syntax(CStrRef filename, VRefParam error_message = null);
+bool f_php_check_syntax(CStrRef filename, VRefParam error_message = uninit_null());
 String f_php_strip_whitespace(CStrRef filename);
 int64_t f_sleep(int seconds);
 void f_usleep(int micro_seconds);

hphp/runtime/ext/ext_mysql.cpp

@@ -740,7 +740,7 @@ Variant mysql_makevalue(CStrRef data, MYSQL_FIELD *mysql_field) {
     //case MYSQL_TYPE_NEWDECIMAL:
     return data.toDouble();
   case MYSQL_TYPE_NULL:
-    return null;
+    return uninit_null();
   default:
     break;
   }
@@ -1592,7 +1592,7 @@ Variant f_mysql_result(CVarRef result, int row,
                     CopyString);
     }
   }
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -1723,7 +1723,7 @@ MySQLFieldInfo *MySQLResult::getFieldInfo(int64_t field) {
 
 Variant MySQLResult::getField(int64_t field) const {
   if (!m_localized || field < 0 || field >= (int64_t)m_current_row->size()) {
-    return null;
+    return uninit_null();
   }
   return *(*m_current_row)[field];
 }

hphp/runtime/ext/ext_mysql.ext_hhvm.cpp

@@ -1677,7 +1677,7 @@ TypedValue * fg1_mysql_fetch_object(TypedValue* rv, HPHP::VM::ActRec* ar, int64_
     break;
   }
   String defVal1 = "stdClass";
-  Array defVal2 = null;
+  Array defVal2 = uninit_null();
   fh_mysql_fetch_object((rv), (args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -1690,7 +1690,7 @@ TypedValue* fg_mysql_fetch_object(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 3LL) {
       if ((count <= 2 || (args-2)->m_type == KindOfArray) && (count <= 1 || IS_STRING_TYPE((args-1)->m_type))) {
         String defVal1 = "stdClass";
-        Array defVal2 = null;
+        Array defVal2 = uninit_null();
         fh_mysql_fetch_object((&(rv)), (args-0), (count > 1) ? (Value*)(args-1) : (Value*)(&defVal1), (count > 2) ? (Value*)(args-2) : (Value*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);

hphp/runtime/ext/ext_mysql.h

@@ -266,89 +266,89 @@ Variant f_mysql_async_wait_actionable(CVarRef items, double timeout);
 String f_mysql_escape_string(CStrRef unescaped_string);
 
 Variant f_mysql_real_escape_string(CStrRef unescaped_string,
-                                   CVarRef link_identifier = null);
+                                   CVarRef link_identifier = uninit_null());
 
 inline String f_mysql_get_client_info() {
   return String(mysql_get_client_info(), CopyString);
 }
 inline Variant f_mysql_set_charset(CStrRef charset,
-                                   CVarRef link_identifier = null) {
+                                   CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
-  if (!conn) return null;
+  if (!conn) return uninit_null();
   return !mysql_set_character_set(conn, charset.data());
 }
-inline Variant f_mysql_ping(CVarRef link_identifier = null) {
+inline Variant f_mysql_ping(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
-  if (!conn) return null;
+  if (!conn) return uninit_null();
   return !mysql_ping(conn);
 }
-inline Variant f_mysql_client_encoding(CVarRef link_identifier = null) {
+inline Variant f_mysql_client_encoding(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return String(mysql_character_set_name(conn), CopyString);
 }
-inline Variant f_mysql_close(CVarRef link_identifier = null) {
+inline Variant f_mysql_close(CVarRef link_identifier = uninit_null()) {
   return MySQL::CloseConn(link_identifier);
 }
 
-Variant f_mysql_errno(CVarRef link_identifier = null);
+Variant f_mysql_errno(CVarRef link_identifier = uninit_null());
 
-Variant f_mysql_error(CVarRef link_identifier = null);
+Variant f_mysql_error(CVarRef link_identifier = uninit_null());
 
-Variant f_mysql_warning_count(CVarRef link_identifier = null);
+Variant f_mysql_warning_count(CVarRef link_identifier = uninit_null());
 
-inline Variant f_mysql_get_host_info(CVarRef link_identifier = null) {
+inline Variant f_mysql_get_host_info(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return String(mysql_get_host_info(conn), CopyString);
 }
-inline Variant f_mysql_get_proto_info(CVarRef link_identifier = null) {
+inline Variant f_mysql_get_proto_info(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return (int64_t)mysql_get_proto_info(conn);
 }
-inline Variant f_mysql_get_server_info(CVarRef link_identifier = null) {
+inline Variant f_mysql_get_server_info(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return String(mysql_get_server_info(conn), CopyString);
 }
-inline Variant f_mysql_info(CVarRef link_identifier = null) {
+inline Variant f_mysql_info(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return String(mysql_info(conn), CopyString);
 }
-inline Variant f_mysql_insert_id(CVarRef link_identifier = null) {
+inline Variant f_mysql_insert_id(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return static_cast<int64_t>(mysql_insert_id(conn));
 }
-inline Variant f_mysql_stat(CVarRef link_identifier = null) {
+inline Variant f_mysql_stat(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return String(mysql_stat(conn), CopyString);
 }
-inline Variant f_mysql_thread_id(CVarRef link_identifier = null) {
+inline Variant f_mysql_thread_id(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return (int64_t)mysql_thread_id(conn);
 }
 inline Variant f_mysql_create_db(CStrRef db,
-                                 CVarRef link_identifier = null) {
+                                 CVarRef link_identifier = uninit_null()) {
   throw NotSupportedException
     (__func__, "Deprecated. Use mysql_query(CREATE DATABASE) instead.");
 }
 inline Variant f_mysql_select_db(CStrRef db,
-                                 CVarRef link_identifier = null) {
+                                 CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return mysql_select_db(conn, db.data()) == 0;
 }
 inline Variant f_mysql_drop_db(CStrRef db,
-                               CVarRef link_identifier = null) {
+                               CVarRef link_identifier = uninit_null()) {
   throw NotSupportedException
     (__func__, "Deprecated. Use mysql_query(DROP DATABASE) instead.");
 }
-inline Variant f_mysql_affected_rows(CVarRef link_identifier = null) {
+inline Variant f_mysql_affected_rows(CVarRef link_identifier = uninit_null()) {
   MYSQL *conn = MySQL::GetConn(link_identifier);
   if (!conn) return false;
   return static_cast<int64_t>(mysql_affected_rows(conn));
@@ -360,35 +360,35 @@ inline Variant f_mysql_affected_rows(CVarRef link_identifier = null) {
 Variant mysql_makevalue(CStrRef data, MYSQL_FIELD *mysql_field);
 
 bool f_mysql_set_timeout(int query_timeout_ms = -1,
-                         CVarRef link_identifier = null);
+                         CVarRef link_identifier = uninit_null());
 
-Variant f_mysql_query(CStrRef query, CVarRef link_identifier = null);
-Variant f_mysql_multi_query(CStrRef query, CVarRef link_identifier = null);
+Variant f_mysql_query(CStrRef query, CVarRef link_identifier = uninit_null());
+Variant f_mysql_multi_query(CStrRef query, CVarRef link_identifier = uninit_null());
 
-bool f_mysql_next_result(CVarRef link_identifier = null);
+bool f_mysql_next_result(CVarRef link_identifier = uninit_null());
 
-bool f_mysql_more_results(CVarRef link_identifier = null);
+bool f_mysql_more_results(CVarRef link_identifier = uninit_null());
 
-Variant f_mysql_fetch_result(CVarRef link_identifier = null);
+Variant f_mysql_fetch_result(CVarRef link_identifier = uninit_null());
 
 Variant f_mysql_unbuffered_query(CStrRef query,
-                                 CVarRef link_identifier = null);
+                                 CVarRef link_identifier = uninit_null());
 inline Variant f_mysql_db_query(CStrRef database, CStrRef query,
-                                CVarRef link_identifier = null) {
+                                CVarRef link_identifier = uninit_null()) {
   throw NotSupportedException
     (__func__, "Deprecated. Use mysql_query() instead.");
 }
-Variant f_mysql_list_dbs(CVarRef link_identifier = null);
+Variant f_mysql_list_dbs(CVarRef link_identifier = uninit_null());
 
 Variant f_mysql_list_tables(CStrRef database,
-                            CVarRef link_identifier = null);
+                            CVarRef link_identifier = uninit_null());
 inline Variant f_mysql_list_fields(CStrRef database_name, CStrRef table_name,
-                                   CVarRef link_identifier = null) {
+                                   CVarRef link_identifier = uninit_null()) {
   throw NotSupportedException
     (__func__, "Deprecated. Use mysql_query(SHOW COLUMNS FROM table "
      "[LIKE 'name']) instead.");
 }
-Variant f_mysql_list_processes(CVarRef link_identifier = null);
+Variant f_mysql_list_processes(CVarRef link_identifier = uninit_null());
 
 ///////////////////////////////////////////////////////////////////////////////
 // row operations
@@ -404,7 +404,7 @@ Variant f_mysql_fetch_array(CVarRef result, int result_type = 3);
 Variant f_mysql_fetch_lengths(CVarRef result);
 
 Variant f_mysql_fetch_object(CVarRef result, CStrRef class_name = "stdClass",
-                             CArrRef params = null);
+                             CArrRef params = uninit_null());
 
 Variant f_mysql_result(CVarRef result, int row, CVarRef field = null_variant);
 

hphp/runtime/ext/ext_network.ext_hhvm.cpp

@@ -713,8 +713,8 @@ TypedValue * fg1_dns_get_record(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t co
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
-  VRefParamValue defVal3 = null;
+  VRefParamValue defVal2 = uninit_null();
+  VRefParamValue defVal3 = uninit_null();
   fh_dns_get_record((rv), (Value*)(args-0), (count > 1) ? (int)(args[-1].m_data.num) : (int)(-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -726,8 +726,8 @@ TypedValue* fg_dns_get_record(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 1LL && count <= 4LL) {
       if ((count <= 1 || (args-1)->m_type == KindOfInt64) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
-        VRefParamValue defVal3 = null;
+        VRefParamValue defVal2 = uninit_null();
+        VRefParamValue defVal3 = uninit_null();
         fh_dns_get_record((&(rv)), (Value*)(args-0), (count > 1) ? (int)(args[-1].m_data.num) : (int)(-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (args-3) : (TypedValue*)(&defVal3));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 4);
@@ -769,7 +769,7 @@ TypedValue * fg1_dns_get_mx(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count)
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   rv->m_data.num = (fh_dns_get_mx((Value*)(args-0), (args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
   return rv;
 }
@@ -781,7 +781,7 @@ TypedValue* fg_dns_get_mx(HPHP::VM::ActRec *ar) {
     if (count >= 2LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_type = KindOfBoolean;
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         rv.m_data.num = (fh_dns_get_mx((Value*)(args-0), (args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 3);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));
@@ -1004,8 +1004,8 @@ TypedValue* fg_headers_sent(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count <= 2LL) {
       rv.m_type = KindOfBoolean;
-      VRefParamValue defVal0 = null;
-      VRefParamValue defVal1 = null;
+      VRefParamValue defVal0 = uninit_null();
+      VRefParamValue defVal1 = uninit_null();
       rv.m_data.num = (fh_headers_sent((count > 0) ? (args-0) : (TypedValue*)(&defVal0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1))) ? 1LL : 0LL;
       frame_free_locals_no_this_inl(ar, 2);
       memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_network.h

@@ -44,24 +44,24 @@ inline bool f_checkdnsrr(CStrRef host, CStrRef type = null_string) {
   return f_dns_check_record(host, type);
 }
 
-Variant f_dns_get_record(CStrRef hostname, int type = -1, VRefParam authns = null,
-                         VRefParam addtl = null);
+Variant f_dns_get_record(CStrRef hostname, int type = -1, VRefParam authns = uninit_null(),
+                         VRefParam addtl = uninit_null());
 
-bool f_dns_get_mx(CStrRef hostname, VRefParam mxhosts, VRefParam weights = null);
+bool f_dns_get_mx(CStrRef hostname, VRefParam mxhosts, VRefParam weights = uninit_null());
 
 inline bool f_getmxrr(CStrRef hostname, VRefParam mxhosts,
-                      VRefParam weight = null) {
+                      VRefParam weight = uninit_null()) {
   return f_dns_get_mx(hostname, ref(mxhosts), weight);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // socket
 
-Variant f_fsockopen(CStrRef hostname, int port = -1, VRefParam errnum = null,
-                    VRefParam errstr = null, double timeout = 0.0);
+Variant f_fsockopen(CStrRef hostname, int port = -1, VRefParam errnum = uninit_null(),
+                    VRefParam errstr = uninit_null(), double timeout = 0.0);
 
-Variant f_pfsockopen(CStrRef hostname, int port = -1, VRefParam errnum = null,
-                     VRefParam errstr = null, double timeout = 0.0);
+Variant f_pfsockopen(CStrRef hostname, int port = -1, VRefParam errnum = uninit_null(),
+                     VRefParam errstr = uninit_null(), double timeout = 0.0);
 
 inline Variant f_socket_get_status(CObjRef stream) {
   return f_stream_get_meta_data(stream);
@@ -85,7 +85,7 @@ Variant f_http_response_code(int response_code = 0);
 
 Array f_headers_list();
 
-bool f_headers_sent(VRefParam file = null, VRefParam line = null);
+bool f_headers_sent(VRefParam file = uninit_null(), VRefParam line = uninit_null());
 
 bool f_header_register_callback(CVarRef callback);
 

hphp/runtime/ext/ext_options.cpp

@@ -99,7 +99,7 @@ Variant f_assert(CVarRef assertion) {
   if (s_option_data->assertBail) {
     throw Assertion();
   }
-  return null;
+  return uninit_null();
 }
 
 int64_t f_dl(CStrRef library) {
@@ -973,7 +973,7 @@ Variant f_version_compare(CStrRef version1, CStrRef version2,
       !strncmp(op, "ne", op_len)) {
     return compare != 0;
   }
-  return null;
+  return uninit_null();
 }
 
 bool f_gc_enabled() {

hphp/runtime/ext/ext_output.ext_hhvm.cpp

@@ -294,7 +294,7 @@ TypedValue * fg1_hphp_set_hardware_events(TypedValue* rv, HPHP::VM::ActRec* ar,
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfBoolean;
   tvCastToStringInPlace(args-0);
-  String defVal0 = null;
+  String defVal0 = uninit_null();
   rv->m_data.num = (fh_hphp_set_hardware_events((count > 0) ? (Value*)(args-0) : (Value*)(&defVal0))) ? 1LL : 0LL;
   return rv;
 }
@@ -306,7 +306,7 @@ TypedValue* fg_hphp_set_hardware_events(HPHP::VM::ActRec *ar) {
     if (count <= 1LL) {
       if ((count <= 0 || IS_STRING_TYPE((args-0)->m_type))) {
         rv.m_type = KindOfBoolean;
-        String defVal0 = null;
+        String defVal0 = uninit_null();
         rv.m_data.num = (fh_hphp_set_hardware_events((count > 0) ? (Value*)(args-0) : (Value*)(&defVal0))) ? 1LL : 0LL;
         frame_free_locals_no_this_inl(ar, 1);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));

hphp/runtime/ext/ext_output.h

@@ -24,7 +24,7 @@
 namespace HPHP {
 ///////////////////////////////////////////////////////////////////////////////
 
-inline bool f_ob_start(CVarRef output_callback = null, int chunk_size = 0,
+inline bool f_ob_start(CVarRef output_callback = uninit_null(), int chunk_size = 0,
                        bool erase = true) {
   // ignoring chunk_size and erase
   g_context->obStart(output_callback);

hphp/runtime/ext/ext_pdo.cpp

@@ -930,12 +930,12 @@ void c_PDO::t___construct(CStrRef dsn, CStrRef username /* = null_string */,
     String name = "pdo.dsn."; name += data_source;
     String ini_dsn;
     if (!IniSetting::Get(name, ini_dsn)) {
-      throw_pdo_exception(null, null, "invalid data source name");
+      throw_pdo_exception(uninit_null(), uninit_null(), "invalid data source name");
     }
     data_source = ini_dsn;
     colon = strchr(data_source.data(), ':');
     if (!colon) {
-      throw_pdo_exception(null, null, "invalid data source name (via INI: %s)",
+      throw_pdo_exception(uninit_null(), uninit_null(), "invalid data source name (via INI: %s)",
                           ini_dsn.data());
     }
   }
@@ -944,12 +944,12 @@ void c_PDO::t___construct(CStrRef dsn, CStrRef username /* = null_string */,
     /* the specified URI holds connection details */
     Variant stream = File::Open(data_source.substr(4), "rb");
     if (same(stream, false)) {
-      throw_pdo_exception(null, null, "invalid data source URI");
+      throw_pdo_exception(uninit_null(), uninit_null(), "invalid data source URI");
     }
     data_source = stream.toObject().getTyped<File>()->readLine(1024);
     colon = strchr(data_source.data(), ':');
     if (!colon) {
-      throw_pdo_exception(null, null, "invalid data source name (via URI)");
+      throw_pdo_exception(uninit_null(), uninit_null(), "invalid data source name (via URI)");
     }
   }
 
@@ -959,7 +959,7 @@ void c_PDO::t___construct(CStrRef dsn, CStrRef username /* = null_string */,
   if (iter == drivers.end()) {
     /* NB: don't want to include the data_source in the error message as
      * it might contain a password */
-    throw_pdo_exception(null, null, "could not find driver");
+    throw_pdo_exception(uninit_null(), uninit_null(), "could not find driver");
   }
   PDODriver *driver = iter->second;
 
@@ -1013,7 +1013,7 @@ void c_PDO::t___construct(CStrRef dsn, CStrRef username /* = null_string */,
         /* need a brand new pdbh */
         m_dbh = driver->createConnection(colon+1, username, password, options);
         if (m_dbh.get() == NULL) {
-          throw_pdo_exception(null, null, "unable to create a connection");
+          throw_pdo_exception(uninit_null(), uninit_null(), "unable to create a connection");
         }
         m_dbh->persistent_id = string(shashkey.data(), shashkey.size());
       }
@@ -1022,7 +1022,7 @@ void c_PDO::t___construct(CStrRef dsn, CStrRef username /* = null_string */,
   if (!m_dbh.get()) {
     m_dbh = driver->createConnection(colon+1, username, password, options);
     if (m_dbh.get() == NULL) {
-      throw_pdo_exception(null, null, "unable to create a connection");
+      throw_pdo_exception(uninit_null(), uninit_null(), "unable to create a connection");
     }
   }
 
@@ -1100,7 +1100,7 @@ Variant c_PDO::t_prepare(CStrRef statement,
 
 bool c_PDO::t_begintransaction() {
   if (m_dbh->in_txn) {
-    throw_pdo_exception(null, null, "There is already an active transaction");
+    throw_pdo_exception(uninit_null(), uninit_null(), "There is already an active transaction");
   }
   if (m_dbh->begin()) {
     m_dbh->in_txn = 1;
@@ -1115,7 +1115,7 @@ bool c_PDO::t_begintransaction() {
 bool c_PDO::t_commit() {
   assert(m_dbh->driver);
   if (!m_dbh->in_txn) {
-    throw_pdo_exception(null, null, "There is no active transaction");
+    throw_pdo_exception(uninit_null(), uninit_null(), "There is no active transaction");
   }
   if (m_dbh->commit()) {
     m_dbh->in_txn = 0;
@@ -1128,7 +1128,7 @@ bool c_PDO::t_commit() {
 bool c_PDO::t_rollback() {
   assert(m_dbh->driver);
   if (!m_dbh->in_txn) {
-    throw_pdo_exception(null, null, "There is no active transaction");
+    throw_pdo_exception(uninit_null(), uninit_null(), "There is no active transaction");
   }
   if (m_dbh->rollback()) {
     m_dbh->in_txn = 0;
@@ -1241,7 +1241,7 @@ bool c_PDO::t_setattribute(int64_t attribute, CVarRef value) {
   }
 
   if (attribute == PDO_ATTR_AUTOCOMMIT) {
-    throw_pdo_exception(null, null,
+    throw_pdo_exception(uninit_null(), uninit_null(),
                         "The auto-commit mode cannot be changed for this "
                         "driver");
   } else if (!m_dbh->support(PDOConnection::MethodSetAttribute)) {
@@ -1351,7 +1351,7 @@ Variant c_PDO::t_errorcode() {
   }
 
   if (m_dbh->error_code[0] == '\0') {
-    return null;
+    return uninit_null();
   }
 
   /**
@@ -1385,7 +1385,7 @@ Array c_PDO::t_errorinfo() {
   if (error_expected_count > error_count) {
     int error_count_diff = error_expected_count - error_count;
     for (int i = 0; i < error_count_diff; i++) {
-      ret.append(null);
+      ret.append(uninit_null());
     }
   }
   return ret;
@@ -1402,7 +1402,7 @@ Variant c_PDO::t_query(CStrRef sql) {
     pdo_raise_impl_error
       (m_dbh, NULL, "HY000",
        "failed to instantiate user supplied statement class");
-    return null;
+    return uninit_null();
   }
   c_PDOStatement *pdostmt = ret.getTyped<c_PDOStatement>();
 
@@ -1415,7 +1415,7 @@ Variant c_PDO::t_query(CStrRef sql) {
     stmt->default_fetch_type = m_dbh->default_fetch_type;
     stmt->active_query_string = stmt->query_string;
     stmt->dbh = m_dbh;
-    stmt->lazy_object_ref = null;
+    stmt->lazy_object_ref = uninit_null();
 
     strcpy(stmt->error_code, PDO_ERR_NONE);
 
@@ -1469,15 +1469,15 @@ Variant c_PDO::t_quote(CStrRef str, int64_t paramtype /* = q_PDO$$PARAM_STR */)
 }
 
 Variant c_PDO::t___wakeup() {
-  throw_pdo_exception(null, null,
+  throw_pdo_exception(uninit_null(), uninit_null(),
                       "You cannot serialize or unserialize PDO instances");
-  return null;
+  return uninit_null();
 }
 
 Variant c_PDO::t___sleep() {
-  throw_pdo_exception(null, null,
+  throw_pdo_exception(uninit_null(), uninit_null(),
                       "You cannot serialize or unserialize PDO instances");
-  return null;
+  return uninit_null();
 }
 
 Array c_PDO::ti_getavailabledrivers(const char* cls) {
@@ -1661,7 +1661,7 @@ static inline void fetch_value(sp_PDOStatement stmt, Variant &dest, int colno,
     case PDO_PARAM_INT:  dest = dest.toInt64();   break;
     case PDO_PARAM_BOOL: dest = dest.toBoolean(); break;
     case PDO_PARAM_STR:  dest = dest.toString();  break;
-    case PDO_PARAM_NULL: dest = null;             break;
+    case PDO_PARAM_NULL: dest = uninit_null();             break;
     }
   }
   if (stmt->dbh->stringify && (dest.isInteger() || dest.isDouble())) {
@@ -2878,7 +2878,7 @@ Variant c_PDOStatement::t_fetchall(int64_t how /* = 0 */,
 
 bool c_PDOStatement::t_bindvalue(CVarRef paramno, CVarRef param,
                                  int64_t type /* = q_PDO$$PARAM_STR */) {
-  return register_bound_param(paramno, param, type, 0, null, m_stmt, true);
+  return register_bound_param(paramno, param, type, 0, uninit_null(), m_stmt, true);
 }
 
 bool c_PDOStatement::t_bindparam(CVarRef paramno, VRefParam param,
@@ -2903,7 +2903,7 @@ int64_t c_PDOStatement::t_rowcount() {
 
 Variant c_PDOStatement::t_errorcode() {
   if (m_stmt->error_code[0] == '\0') {
-    return null;
+    return uninit_null();
   }
   return String(m_stmt->error_code, CopyString);
 }
@@ -2921,7 +2921,7 @@ Array c_PDOStatement::t_errorinfo() {
   if (error_expected_count > error_count) {
     int error_count_diff = error_expected_count - error_count;
     for (int i = 0; i < error_count_diff; i++) {
-      ret.append(null);
+      ret.append(uninit_null());
     }
   }
   return ret;
@@ -3112,13 +3112,13 @@ Variant c_PDOStatement::t_next() {
   } else {
     ++m_rowIndex;
   }
-  return null;
+  return uninit_null();
 }
 
 Variant c_PDOStatement::t_rewind() {
   m_rowIndex = -1;
   t_next();
-  return null;
+  return uninit_null();
 }
 
 Variant c_PDOStatement::t_valid() {
@@ -3126,15 +3126,15 @@ Variant c_PDOStatement::t_valid() {
 }
 
 Variant c_PDOStatement::t___wakeup() {
-  throw_pdo_exception(null, null, "You cannot serialize or unserialize "
+  throw_pdo_exception(uninit_null(), uninit_null(), "You cannot serialize or unserialize "
                       "PDOStatement instances");
-  return null;
+  return uninit_null();
 }
 
 Variant c_PDOStatement::t___sleep() {
-  throw_pdo_exception(null, null, "You cannot serialize or unserialize "
+  throw_pdo_exception(uninit_null(), uninit_null(), "You cannot serialize or unserialize "
                       "PDOStatement instances");
-  return null;
+  return uninit_null();
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_pdo.h

@@ -156,12 +156,12 @@ class c_PDOStatement : public ExtObjectData, public Sweepable {
   public: void t___construct();
   public: Variant t_execute(CArrRef params = null_array);
   public: Variant t_fetch(int64_t how = 0, int64_t orientation = q_PDO$$FETCH_ORI_NEXT, int64_t offset = 0);
-  public: Variant t_fetchobject(CStrRef class_name = null_string, CVarRef ctor_args = null);
+  public: Variant t_fetchobject(CStrRef class_name = null_string, CVarRef ctor_args = uninit_null());
   public: Variant t_fetchcolumn(int64_t column_numner = 0);
-  public: Variant t_fetchall(int64_t how = 0, CVarRef class_name = null, CVarRef ctor_args = null);
+  public: Variant t_fetchall(int64_t how = 0, CVarRef class_name = uninit_null(), CVarRef ctor_args = uninit_null());
   public: bool t_bindvalue(CVarRef paramno, CVarRef param, int64_t type = q_PDO$$PARAM_STR);
-  public: bool t_bindparam(CVarRef paramno, VRefParam param, int64_t type = q_PDO$$PARAM_STR, int64_t max_value_len = 0, CVarRef driver_params = null);
-  public: bool t_bindcolumn(CVarRef paramno, VRefParam param, int64_t type = q_PDO$$PARAM_STR, int64_t max_value_len = 0, CVarRef driver_params = null);
+  public: bool t_bindparam(CVarRef paramno, VRefParam param, int64_t type = q_PDO$$PARAM_STR, int64_t max_value_len = 0, CVarRef driver_params = uninit_null());
+  public: bool t_bindcolumn(CVarRef paramno, VRefParam param, int64_t type = q_PDO$$PARAM_STR, int64_t max_value_len = 0, CVarRef driver_params = uninit_null());
   public: int64_t t_rowcount();
   public: Variant t_errorcode();
   public: Array t_errorinfo();

hphp/runtime/ext/ext_preg.ext_hhvm.cpp

@@ -126,7 +126,7 @@ TypedValue * fg1_preg_match(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count)
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_preg_match((rv), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(0), (count > 4) ? (int)(args[-4].m_data.num) : (int)(0));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -138,7 +138,7 @@ TypedValue* fg_preg_match(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 5LL) {
       if ((count <= 4 || (args-4)->m_type == KindOfInt64) && (count <= 3 || (args-3)->m_type == KindOfInt64) && IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_preg_match((&(rv)), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(0), (count > 4) ? (int)(args[-4].m_data.num) : (int)(0));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 5);
@@ -253,7 +253,7 @@ TypedValue * fg1_preg_replace(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t coun
 TypedValue * fg1_preg_replace(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToInt64InPlace(args-3);
-  VRefParamValue defVal4 = null;
+  VRefParamValue defVal4 = uninit_null();
   fh_preg_replace((rv), (args-0), (args-1), (args-2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(-1), (count > 4) ? (args-4) : (TypedValue*)(&defVal4));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -265,7 +265,7 @@ TypedValue* fg_preg_replace(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 3LL && count <= 5LL) {
       if ((count <= 3 || (args-3)->m_type == KindOfInt64)) {
-        VRefParamValue defVal4 = null;
+        VRefParamValue defVal4 = uninit_null();
         fh_preg_replace((&(rv)), (args-0), (args-1), (args-2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(-1), (count > 4) ? (args-4) : (TypedValue*)(&defVal4));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 5);
@@ -309,7 +309,7 @@ TypedValue * fg1_preg_replace_callback(TypedValue* rv, HPHP::VM::ActRec* ar, int
 TypedValue * fg1_preg_replace_callback(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   tvCastToInt64InPlace(args-3);
-  VRefParamValue defVal4 = null;
+  VRefParamValue defVal4 = uninit_null();
   fh_preg_replace_callback((rv), (args-0), (args-1), (args-2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(-1), (count > 4) ? (args-4) : (TypedValue*)(&defVal4));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -321,7 +321,7 @@ TypedValue* fg_preg_replace_callback(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 3LL && count <= 5LL) {
       if ((count <= 3 || (args-3)->m_type == KindOfInt64)) {
-        VRefParamValue defVal4 = null;
+        VRefParamValue defVal4 = uninit_null();
         fh_preg_replace_callback((&(rv)), (args-0), (args-1), (args-2), (count > 3) ? (int)(args[-3].m_data.num) : (int)(-1), (count > 4) ? (args-4) : (TypedValue*)(&defVal4));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 5);
@@ -656,7 +656,7 @@ TypedValue * fg1_ereg(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_ereg((rv), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -668,7 +668,7 @@ TypedValue* fg_ereg(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_ereg((&(rv)), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -720,7 +720,7 @@ TypedValue * fg1_eregi(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   if (!IS_STRING_TYPE((args-0)->m_type)) {
     tvCastToStringInPlace(args-0);
   }
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal2 = uninit_null();
   fh_eregi((rv), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_type == KindOfUninit) rv->m_type = KindOfNull;
   return rv;
@@ -732,7 +732,7 @@ TypedValue* fg_eregi(HPHP::VM::ActRec *ar) {
     TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
     if (count >= 2LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-1)->m_type) && IS_STRING_TYPE((args-0)->m_type)) {
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal2 = uninit_null();
         fh_eregi((&(rv)), (Value*)(args-0), (Value*)(args-1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_type == KindOfUninit) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);

hphp/runtime/ext/ext_preg.h

@@ -28,18 +28,18 @@ namespace HPHP {
 
 Variant f_preg_grep(CStrRef pattern, CArrRef input, int flags = 0);
 
-Variant f_preg_match(CStrRef pattern, CStrRef subject, VRefParam matches = null,
+Variant f_preg_match(CStrRef pattern, CStrRef subject, VRefParam matches = uninit_null(),
                      int flags = 0, int offset = 0);
 
 Variant f_preg_match_all(CStrRef pattern, CStrRef subject, VRefParam matches,
                          int flags = 0, int offset = 0);
 
 Variant f_preg_replace(CVarRef pattern, CVarRef replacement, CVarRef subject,
-                       int limit = -1, VRefParam count = null);
+                       int limit = -1, VRefParam count = uninit_null());
 
 Variant f_preg_replace_callback(CVarRef pattern, CVarRef callback,
                                 CVarRef subject, int limit = -1,
-                                VRefParam count = null);
+                                VRefParam count = uninit_null());
 
 Variant f_preg_split(CVarRef pattern, CVarRef subject, int limit = -1,
                      int flags = 0);
@@ -53,8 +53,8 @@ int64_t f_preg_last_error();
 
 String f_ereg_replace(CStrRef pattern, CStrRef replacement, CStrRef str);
 String f_eregi_replace(CStrRef pattern, CStrRef replacement, CStrRef str);
-Variant f_ereg(CStrRef pattern, CStrRef str, VRefParam regs = null);
-Variant f_eregi(CStrRef pattern, CStrRef str, VRefParam regs = null);
+Variant f_ereg(CStrRef pattern, CStrRef str, VRefParam regs = uninit_null());
+Variant f_eregi(CStrRef pattern, CStrRef str, VRefParam regs = uninit_null());
 Variant f_split(CStrRef pattern, CStrRef str, int limit = -1);
 Variant f_spliti(CStrRef pattern, CStrRef str, int limit = -1);
 String f_sql_regcase(CStrRef str);

hphp/runtime/ext/ext_process.ext_hhvm.cpp

@@ -523,8 +523,8 @@ TypedValue * fg1_exec(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfString;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
-  VRefParamValue defVal2 = null;
+  VRefParamValue defVal1 = uninit_null();
+  VRefParamValue defVal2 = uninit_null();
   fh_exec((Value*)(rv), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
   if (rv->m_data.num == 0LL) rv->m_type = KindOfNull;
   return rv;
@@ -537,8 +537,8 @@ TypedValue* fg_exec(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 3LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_type = KindOfString;
-        VRefParamValue defVal1 = null;
-        VRefParamValue defVal2 = null;
+        VRefParamValue defVal1 = uninit_null();
+        VRefParamValue defVal2 = uninit_null();
         fh_exec((Value*)(&(rv)), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1), (count > 2) ? (args-2) : (TypedValue*)(&defVal2));
         if (rv.m_data.num == 0LL) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 3);
@@ -579,7 +579,7 @@ TypedValue * fg1_passthru(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   rv->m_data.num = 0LL;
   rv->m_type = KindOfNull;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   fh_passthru((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
   return rv;
 }
@@ -592,7 +592,7 @@ TypedValue* fg_passthru(HPHP::VM::ActRec *ar) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_data.num = 0LL;
         rv.m_type = KindOfNull;
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         fh_passthru((Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
         frame_free_locals_no_this_inl(ar, 2);
         memcpy(&ar->m_r, &rv, sizeof(TypedValue));
@@ -633,7 +633,7 @@ TypedValue * fg1_system(TypedValue* rv, HPHP::VM::ActRec* ar, int64_t count) {
   TypedValue* args UNUSED = ((TypedValue*)ar) - 1;
   rv->m_type = KindOfString;
   tvCastToStringInPlace(args-0);
-  VRefParamValue defVal1 = null;
+  VRefParamValue defVal1 = uninit_null();
   fh_system((Value*)(rv), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
   if (rv->m_data.num == 0LL) rv->m_type = KindOfNull;
   return rv;
@@ -646,7 +646,7 @@ TypedValue* fg_system(HPHP::VM::ActRec *ar) {
     if (count >= 1LL && count <= 2LL) {
       if (IS_STRING_TYPE((args-0)->m_type)) {
         rv.m_type = KindOfString;
-        VRefParamValue defVal1 = null;
+        VRefParamValue defVal1 = uninit_null();
         fh_system((Value*)(&(rv)), (Value*)(args-0), (count > 1) ? (args-1) : (TypedValue*)(&defVal1));
         if (rv.m_data.num == 0LL) rv.m_type = KindOfNull;
         frame_free_locals_no_this_inl(ar, 2);