diff --git a/dom/plugins/base/nsJSNPRuntime.cpp b/dom/plugins/base/nsJSNPRuntime.cpp
index d602e91f997..d5b582e8655 100644
--- a/dom/plugins/base/nsJSNPRuntime.cpp
+++ b/dom/plugins/base/nsJSNPRuntime.cpp
@@ -1014,11 +1014,11 @@ nsJSObjWrapper::GetNewOrUsed(NPP npp, JSContext *cx, JS::Handle<JSObject*> obj)
 
   JSObjWrapperTable::AddPtr p = sJSObjWrappers.lookupForAdd(key);
 
-  if (p/* && p->value*/) {
-    MOZ_ASSERT(p->value);
+  if (p/* && p->value()*/) {
+    MOZ_ASSERT(p->value());
     // Found a live nsJSObjWrapper, return it.
 
-    return _retainobject(p->value);
+    return _retainobject(p->value());
   }
 
   // No existing nsJSObjWrapper, create one.
@@ -1873,7 +1873,7 @@ nsJSNPRuntime::OnPluginDestroy(NPP npp)
 {
   if (sJSObjWrappers.initialized()) {
     for (JSObjWrapperTable::Enum e(sJSObjWrappers); !e.empty(); e.popFront()) {
-      nsJSObjWrapper *npobj = e.front().value;
+      nsJSObjWrapper *npobj = e.front().value();
       MOZ_ASSERT(npobj->_class == &nsJSObjWrapper::sJSObjWrapperNPClass);
       if (npobj->mNpp == npp) {
         npobj->ClearJSObject();
diff --git a/js/ipc/JavaScriptShared.cpp b/js/ipc/JavaScriptShared.cpp
index 2262a0ea1cb..0023126459c 100644
--- a/js/ipc/JavaScriptShared.cpp
+++ b/js/ipc/JavaScriptShared.cpp
@@ -30,9 +30,9 @@ void
 ObjectStore::trace(JSTracer *trc)
 {
     for (ObjectTable::Range r(table_.all()); !r.empty(); r.popFront()) {
-        DebugOnly<JSObject *> prior = r.front().value.get();
-        JS_CallHeapObjectTracer(trc, &r.front().value, "ipc-object");
-        MOZ_ASSERT(r.front().value == prior);
+        DebugOnly<JSObject *> prior = r.front().value().get();
+        JS_CallHeapObjectTracer(trc, &r.front().value(), "ipc-object");
+        MOZ_ASSERT(r.front().value() == prior);
     }
 }
 
@@ -42,7 +42,7 @@ ObjectStore::find(ObjectId id)
     ObjectTable::Ptr p = table_.lookup(id);
     if (!p)
         return nullptr;
-    return p->value;
+    return p->value();
 }
 
 bool
@@ -82,9 +82,9 @@ void
 ObjectIdCache::trace(JSTracer *trc)
 {
     for (ObjectIdTable::Range r(table_->all()); !r.empty(); r.popFront()) {
-        JSObject *obj = r.front().key;
+        JSObject *obj = r.front().key();
         JS_CallObjectTracer(trc, &obj, "ipc-id");
-        MOZ_ASSERT(obj == r.front().key);
+        MOZ_ASSERT(obj == r.front().key());
     }
 }
 
@@ -94,7 +94,7 @@ ObjectIdCache::find(JSObject *obj)
     ObjectIdTable::Ptr p = table_->lookup(obj);
     if (!p)
         return 0;
-    return p->value;
+    return p->value();
 }
 
 bool
diff --git a/js/public/HashTable.h b/js/public/HashTable.h
index 03265f5d1b8..f650af7569b 100644
--- a/js/public/HashTable.h
+++ b/js/public/HashTable.h
@@ -60,8 +60,8 @@ class HashMap
     struct MapHashPolicy : HashPolicy
     {
         typedef Key KeyType;
-        static const Key &getKey(TableEntry &e) { return e.key; }
-        static void setKey(TableEntry &e, Key &k) { HashPolicy::rekey(const_cast<Key &>(e.key), k); }
+        static const Key &getKey(TableEntry &e) { return e.key(); }
+        static void setKey(TableEntry &e, Key &k) { HashPolicy::rekey(e.mutableKey(), k); }
     };
 
     typedef detail::HashTable<TableEntry, MapHashPolicy, AllocPolicy> Impl;
@@ -151,7 +151,7 @@ class HashMap
     template<typename KeyInput, typename ValueInput>
     bool relookupOrAdd(AddPtr &p, KeyInput &&k, ValueInput &&v) {
         Entry e(mozilla::Forward<KeyInput>(k), mozilla::Forward<ValueInput>(v));
-        return impl.relookupOrAdd(p, e.key, mozilla::Move(e));
+        return impl.relookupOrAdd(p, e.key(), mozilla::Move(e));
     }
 
     // |all()| returns a Range containing |count()| elements. E.g.:
@@ -223,7 +223,7 @@ class HashMap
     bool put(KeyInput &&k, ValueInput &&v) {
         AddPtr p = lookupForAdd(k);
         if (p) {
-            p->value = mozilla::Forward<ValueInput>(v);
+            p->value() = mozilla::Forward<ValueInput>(v);
             return true;
         }
         return add(p, mozilla::Forward<KeyInput>(k), mozilla::Forward<ValueInput>(v));
@@ -233,7 +233,7 @@ class HashMap
     template<typename KeyInput, typename ValueInput>
     bool putNew(KeyInput &&k, ValueInput &&v) {
         Entry e(mozilla::Forward<KeyInput>(k), mozilla::Forward<ValueInput>(v));
-        return impl.putNew(e.key, mozilla::Move(e));
+        return impl.putNew(e.key(), mozilla::Move(e));
     }
 
     // Add (k,defaultValue) if |k| is not found. Return a false-y Ptr on oom.
@@ -616,25 +616,37 @@ struct DefaultHasher<float>
 template <class Key, class Value>
 class HashMapEntry
 {
+    Key key_;
+    Value value_;
+
     template <class, class, class> friend class detail::HashTable;
     template <class> friend class detail::HashTableEntry;
+    template <class, class, class, class> friend class HashMap;
 
-    HashMapEntry(const HashMapEntry &) MOZ_DELETE;
-    void operator=(const HashMapEntry &) MOZ_DELETE;
+    Key & mutableKey() { return key_; }
 
   public:
     template<typename KeyInput, typename ValueInput>
     HashMapEntry(KeyInput &&k, ValueInput &&v)
-      : key(mozilla::Forward<KeyInput>(k)), value(mozilla::Forward<ValueInput>(v)) { }
+      : key_(mozilla::Forward<KeyInput>(k)),
+        value_(mozilla::Forward<ValueInput>(v))
+    {}
 
     HashMapEntry(HashMapEntry &&rhs)
-      : key(mozilla::Move(const_cast<Key &>(rhs.key))), value(mozilla::Move(rhs.value)) { }
+      : key_(mozilla::Move(rhs.key_)),
+        value_(mozilla::Move(rhs.value_))
+    {}
 
     typedef Key KeyType;
     typedef Value ValueType;
 
-    const Key key;
-    Value value;
+    const Key & key() const { return key_; }
+    const Value & value() const { return value_; }
+    Value & value() { return value_; }
+
+  private:
+    HashMapEntry(const HashMapEntry &) MOZ_DELETE;
+    void operator=(const HashMapEntry &) MOZ_DELETE;
 };
 
 } // namespace js
diff --git a/js/public/MemoryMetrics.h b/js/public/MemoryMetrics.h
index f758f52a96e..d4d21050932 100644
--- a/js/public/MemoryMetrics.h
+++ b/js/public/MemoryMetrics.h
@@ -343,13 +343,13 @@ struct ZoneStats : js::ZoneStatsPod
         MOZ_ASSERT(other.notableStrings.empty());
 
         for (StringsHashMap::Range r = other.strings.all(); !r.empty(); r.popFront()) {
-            StringsHashMap::AddPtr p = strings.lookupForAdd(r.front().key);
+            StringsHashMap::AddPtr p = strings.lookupForAdd(r.front().key());
             if (p) {
                 // We've seen this string before; add its size to our tally.
-                p->value.add(r.front().value);
+                p->value().add(r.front().value());
             } else {
                 // We haven't seen this string before; add it to the hashtable.
-                strings.add(p, r.front().key, r.front().value);
+                strings.add(p, r.front().key(), r.front().value());
             }
         }
     }
diff --git a/js/src/ctypes/CTypes.cpp b/js/src/ctypes/CTypes.cpp
index fe9bdba78a0..c331c4a2a33 100644
--- a/js/src/ctypes/CTypes.cpp
+++ b/js/src/ctypes/CTypes.cpp
@@ -2923,14 +2923,14 @@ BuildTypeSource(JSContext* cx,
       break;
 
     for (FieldInfoHash::Range r = fields->all(); !r.empty(); r.popFront())
-      fieldsArray[r.front().value.mIndex] = &r.front();
+      fieldsArray[r.front().value().mIndex] = &r.front();
 
     for (size_t i = 0; i < length; ++i) {
       const FieldInfoHash::Entry* entry = fieldsArray[i];
       AppendString(result, "{ \"");
-      AppendString(result, entry->key);
+      AppendString(result, entry->key());
       AppendString(result, "\": ");
-      BuildTypeSource(cx, entry->value.mType, true, result);
+      BuildTypeSource(cx, entry->value().mType, true, result);
       AppendString(result, " }");
       if (i != length - 1)
         AppendString(result, ", ");
@@ -3073,19 +3073,19 @@ BuildDataSource(JSContext* cx,
       return false;
 
     for (FieldInfoHash::Range r = fields->all(); !r.empty(); r.popFront())
-      fieldsArray[r.front().value.mIndex] = &r.front();
+      fieldsArray[r.front().value().mIndex] = &r.front();
 
     for (size_t i = 0; i < length; ++i) {
       const FieldInfoHash::Entry* entry = fieldsArray[i];
 
       if (isImplicit) {
         AppendString(result, "\"");
-        AppendString(result, entry->key);
+        AppendString(result, entry->key());
         AppendString(result, "\": ");
       }
 
-      char* fieldData = static_cast<char*>(data) + entry->value.mOffset;
-      RootedObject entryType(cx, entry->value.mType);
+      char* fieldData = static_cast<char*>(data) + entry->value().mOffset;
+      RootedObject entryType(cx, entry->value().mType);
       if (!BuildDataSource(cx, entryType, fieldData, true, result))
         return false;
 
@@ -3352,11 +3352,11 @@ CType::Trace(JSTracer* trc, JSObject* obj)
     FieldInfoHash* fields =
       static_cast<FieldInfoHash*>(JSVAL_TO_PRIVATE(slot));
     for (FieldInfoHash::Enum e(*fields); !e.empty(); e.popFront()) {
-      JSString *key = e.front().key;
+      JSString *key = e.front().key();
       JS_CallStringTracer(trc, &key, "fieldName");
-      if (key != e.front().key)
+      if (key != e.front().key())
           e.rekeyFront(JS_ASSERT_STRING_IS_FLAT(key));
-      JS_CallHeapObjectTracer(trc, &e.front().value.mType, "fieldType");
+      JS_CallHeapObjectTracer(trc, &e.front().value().mType, "fieldType");
     }
 
     break;
@@ -4931,10 +4931,10 @@ StructType::BuildFFIType(JSContext* cx, JSObject* obj)
 
     for (FieldInfoHash::Range r = fields->all(); !r.empty(); r.popFront()) {
       const FieldInfoHash::Entry& entry = r.front();
-      ffi_type* fieldType = CType::GetFFIType(cx, entry.value.mType);
+      ffi_type* fieldType = CType::GetFFIType(cx, entry.value().mType);
       if (!fieldType)
         return nullptr;
-      elements[entry.value.mIndex] = fieldType;
+      elements[entry.value().mIndex] = fieldType;
     }
 
   } else {
@@ -5072,7 +5072,7 @@ StructType::ConstructData(JSContext* cx,
   // ImplicitConvert each field.
   if (args.length() == fields->count()) {
     for (FieldInfoHash::Range r = fields->all(); !r.empty(); r.popFront()) {
-      const FieldInfo& field = r.front().value;
+      const FieldInfo& field = r.front().value();
       STATIC_ASSUME(field.mIndex < fields->count());  /* Quantified invariant */
       if (!ImplicitConvert(cx, args[field.mIndex], field.mType,
              buffer + field.mOffset,
@@ -5108,7 +5108,7 @@ StructType::LookupField(JSContext* cx, JSObject* obj, JSFlatString *name)
 
   FieldInfoHash::Ptr ptr = GetFieldInfo(obj)->lookup(name);
   if (ptr)
-    return &ptr->value;
+    return &ptr->value();
 
   JSAutoByteString bytes(cx, name);
   if (!bytes)
@@ -5136,8 +5136,8 @@ StructType::BuildFieldsArray(JSContext* cx, JSObject* obj)
   for (FieldInfoHash::Range r = fields->all(); !r.empty(); r.popFront()) {
     const FieldInfoHash::Entry& entry = r.front();
     // Add the field descriptor to the array.
-    if (!AddFieldToArray(cx, &fieldsVec[entry.value.mIndex],
-                         entry.key, entry.value.mType))
+    if (!AddFieldToArray(cx, &fieldsVec[entry.value().mIndex],
+                         entry.key(), entry.value().mType))
       return nullptr;
   }
 
diff --git a/js/src/ds/InlineMap.h b/js/src/ds/InlineMap.h
index 4d623d2c971..41938e2c265 100644
--- a/js/src/ds/InlineMap.h
+++ b/js/src/ds/InlineMap.h
@@ -134,12 +134,12 @@ class InlineMap
 
         K &key() {
             JS_ASSERT(found());
-            return isInlinePtr ? inlPtr->key : mapPtr->key;
+            return isInlinePtr ? inlPtr->key : mapPtr->key();
         }
 
         V &value() {
             JS_ASSERT(found());
-            return isInlinePtr ? inlPtr->value : mapPtr->value;
+            return isInlinePtr ? inlPtr->value : mapPtr->value();
         }
     }; /* class Ptr */
 
@@ -178,7 +178,7 @@ class InlineMap
             JS_ASSERT(found());
             if (isInlinePtr)
                 return inlAddPtr->value;
-            return mapAddPtr->value;
+            return mapAddPtr->value();
         }
     }; /* class AddPtr */
 
@@ -356,7 +356,7 @@ class InlineMap
             JS_ASSERT(!empty());
             if (isInlineRange())
                 return Entry(cur->key, cur->value);
-            return Entry(mapRange.front().key, mapRange.front().value);
+            return Entry(mapRange.front().key(), mapRange.front().value());
         }
 
         void popFront() {
diff --git a/js/src/frontend/ParseMaps.cpp b/js/src/frontend/ParseMaps.cpp
index b86da8ab8e0..ec670eaa490 100644
--- a/js/src/frontend/ParseMaps.cpp
+++ b/js/src/frontend/ParseMaps.cpp
@@ -115,8 +115,8 @@ frontend::InitAtomMap(frontend::AtomIndexMap *indices, HeapPtrAtom *atoms)
         typedef AtomIndexMap::WordMap WordMap;
         const WordMap &wm = indices->asMap();
         for (WordMap::Range r = wm.all(); !r.empty(); r.popFront()) {
-            JSAtom *atom = r.front().key;
-            jsatomid index = r.front().value;
+            JSAtom *atom = r.front().key();
+            jsatomid index = r.front().value();
             JS_ASSERT(index < indices->count());
             atoms[index].init(atom);
         }
diff --git a/js/src/gc/RootMarking.cpp b/js/src/gc/RootMarking.cpp
index d6ceb8b6ab6..0f7ba5f4443 100644
--- a/js/src/gc/RootMarking.cpp
+++ b/js/src/gc/RootMarking.cpp
@@ -474,11 +474,11 @@ AutoGCRooter::trace(JSTracer *trc)
       case OBJOBJHASHMAP: {
         AutoObjectObjectHashMap::HashMapImpl &map = static_cast<AutoObjectObjectHashMap *>(this)->map;
         for (AutoObjectObjectHashMap::Enum e(map); !e.empty(); e.popFront()) {
-            MarkObjectRoot(trc, &e.front().value, "AutoObjectObjectHashMap value");
-            JS_SET_TRACING_LOCATION(trc, (void *)&e.front().key);
-            JSObject *key = e.front().key;
+            MarkObjectRoot(trc, &e.front().value(), "AutoObjectObjectHashMap value");
+            JS_SET_TRACING_LOCATION(trc, (void *)&e.front().key());
+            JSObject *key = e.front().key();
             MarkObjectRoot(trc, &key, "AutoObjectObjectHashMap key");
-            if (key != e.front().key)
+            if (key != e.front().key())
                 e.rekeyFront(key);
         }
         return;
@@ -488,9 +488,9 @@ AutoGCRooter::trace(JSTracer *trc)
         AutoObjectUnsigned32HashMap *self = static_cast<AutoObjectUnsigned32HashMap *>(this);
         AutoObjectUnsigned32HashMap::HashMapImpl &map = self->map;
         for (AutoObjectUnsigned32HashMap::Enum e(map); !e.empty(); e.popFront()) {
-            JSObject *key = e.front().key;
+            JSObject *key = e.front().key();
             MarkObjectRoot(trc, &key, "AutoObjectUnsignedHashMap key");
-            if (key != e.front().key)
+            if (key != e.front().key())
                 e.rekeyFront(key);
         }
         return;
@@ -684,16 +684,18 @@ js::gc::MarkRuntime(JSTracer *trc, bool useSavedRoots)
 
     for (RootRange r = rt->gcRootsHash.all(); !r.empty(); r.popFront()) {
         const RootEntry &entry = r.front();
-        const char *name = entry.value.name ? entry.value.name : "root";
-        if (entry.value.type == JS_GC_ROOT_VALUE_PTR) {
-            MarkValueRoot(trc, reinterpret_cast<Value *>(entry.key), name);
-        } else if (*reinterpret_cast<void **>(entry.key)){
-            if (entry.value.type == JS_GC_ROOT_STRING_PTR)
-                MarkStringRoot(trc, reinterpret_cast<JSString **>(entry.key), name);
-            else if (entry.value.type == JS_GC_ROOT_OBJECT_PTR)
-                MarkObjectRoot(trc, reinterpret_cast<JSObject **>(entry.key), name);
-            else if (entry.value.type == JS_GC_ROOT_SCRIPT_PTR)
-                MarkScriptRoot(trc, reinterpret_cast<JSScript **>(entry.key), name);
+        const char *name = entry.value().name ? entry.value().name : "root";
+        JSGCRootType type = entry.value().type;
+        void *key = entry.key();
+        if (type == JS_GC_ROOT_VALUE_PTR) {
+            MarkValueRoot(trc, reinterpret_cast<Value *>(key), name);
+        } else if (*reinterpret_cast<void **>(key)){
+            if (type == JS_GC_ROOT_STRING_PTR)
+                MarkStringRoot(trc, reinterpret_cast<JSString **>(key), name);
+            else if (type == JS_GC_ROOT_OBJECT_PTR)
+                MarkObjectRoot(trc, reinterpret_cast<JSObject **>(key), name);
+            else if (type == JS_GC_ROOT_SCRIPT_PTR)
+                MarkScriptRoot(trc, reinterpret_cast<JSScript **>(key), name);
             else
                 MOZ_ASSUME_UNREACHABLE("unexpected js::RootInfo::type value");
         }
diff --git a/js/src/jit/AsmJS.cpp b/js/src/jit/AsmJS.cpp
index 90d04f6a908..f1e1af20586 100644
--- a/js/src/jit/AsmJS.cpp
+++ b/js/src/jit/AsmJS.cpp
@@ -1396,13 +1396,14 @@ class MOZ_STACK_CLASS ModuleCompiler
 
     const Global *lookupGlobal(PropertyName *name) const {
         if (GlobalMap::Ptr p = globals_.lookup(name))
-            return p->value;
+            return p->value();
         return nullptr;
     }
     Func *lookupFunction(PropertyName *name) {
         if (GlobalMap::Ptr p = globals_.lookup(name)) {
-            if (p->value->which() == Global::Function)
-                return functions_[p->value->funcIndex()];
+            Global *value = p->value();
+            if (value->which() == Global::Function)
+                return functions_[value->funcIndex()];
         }
         return nullptr;
     }
@@ -1420,7 +1421,7 @@ class MOZ_STACK_CLASS ModuleCompiler
     }
     bool lookupStandardLibraryMathName(PropertyName *name, AsmJSMathBuiltin *mathBuiltin) const {
         if (MathNameMap::Ptr p = standardLibraryMathNames_.lookup(name)) {
-            *mathBuiltin = p->value;
+            *mathBuiltin = p->value();
             return true;
         }
         return false;
@@ -1551,7 +1552,7 @@ class MOZ_STACK_CLASS ModuleCompiler
         ExitDescriptor exitDescriptor(name, Move(sig));
         ExitMap::AddPtr p = exits_.lookupForAdd(exitDescriptor);
         if (p) {
-            *exitIndex = p->value;
+            *exitIndex = p->value();
             return true;
         }
         if (!module_->addExit(ffiIndex, exitIndex))
@@ -1979,7 +1980,7 @@ class FunctionCompiler
     const Local *lookupLocal(PropertyName *name) const
     {
         if (LocalMap::Ptr p = locals_.lookup(name))
-            return &p->value;
+            return &p->value();
         return nullptr;
     }
 
@@ -2536,7 +2537,7 @@ class FunctionCompiler
     {
         bool createdJoinBlock = false;
         if (UnlabeledBlockMap::Ptr p = unlabeledContinues_.lookup(pn)) {
-            if (!bindBreaksOrContinues(&p->value, &createdJoinBlock, pn))
+            if (!bindBreaksOrContinues(&p->value(), &createdJoinBlock, pn))
                 return false;
             unlabeledContinues_.remove(p);
         }
@@ -2698,7 +2699,7 @@ class FunctionCompiler
         const LabelVector &labels = *maybeLabels;
         for (unsigned i = 0; i < labels.length(); i++) {
             if (LabeledBlockMap::Ptr p = map->lookup(labels[i])) {
-                if (!bindBreaksOrContinues(&p->value, createdJoinBlock, pn))
+                if (!bindBreaksOrContinues(&p->value(), createdJoinBlock, pn))
                     return false;
                 map->remove(p);
             }
@@ -2717,7 +2718,7 @@ class FunctionCompiler
             if (!map->add(p, key, Move(empty)))
                 return false;
         }
-        if (!p->value.append(curBlock_))
+        if (!p->value().append(curBlock_))
             return false;
         curBlock_ = nullptr;
         return true;
@@ -2727,7 +2728,7 @@ class FunctionCompiler
     {
         bool createdJoinBlock = false;
         if (UnlabeledBlockMap::Ptr p = unlabeledBreaks_.lookup(pn)) {
-            if (!bindBreaksOrContinues(&p->value, &createdJoinBlock, pn))
+            if (!bindBreaksOrContinues(&p->value(), &createdJoinBlock, pn))
                 return false;
             unlabeledBreaks_.remove(p);
         }
@@ -6373,7 +6374,7 @@ GenerateStubs(ModuleCompiler &m)
     // The order of the iterations here is non-deterministic, since
     // m.allExits() is a hash keyed by pointer values!
     for (ModuleCompiler::ExitMap::Range r = m.allExits(); !r.empty(); r.popFront()) {
-        GenerateFFIExit(m, r.front().key, r.front().value, &throwLabel);
+        GenerateFFIExit(m, r.front().key(), r.front().value(), &throwLabel);
         if (m.masm().oom())
             return false;
     }
diff --git a/js/src/jit/BaselineJIT.cpp b/js/src/jit/BaselineJIT.cpp
index 3a67e888db3..44ed04a7989 100644
--- a/js/src/jit/BaselineJIT.cpp
+++ b/js/src/jit/BaselineJIT.cpp
@@ -891,7 +891,7 @@ void
 jit::JitCompartment::toggleBaselineStubBarriers(bool enabled)
 {
     for (ICStubCodeMap::Enum e(*stubCodes_); !e.empty(); e.popFront()) {
-        IonCode *code = *e.front().value.unsafeGet();
+        IonCode *code = *e.front().value().unsafeGet();
         code->togglePreBarriers(enabled);
     }
 }
diff --git a/js/src/jit/Ion.cpp b/js/src/jit/Ion.cpp
index b2cace2c786..f2ef810ad1f 100644
--- a/js/src/jit/Ion.cpp
+++ b/js/src/jit/Ion.cpp
@@ -603,7 +603,7 @@ JitRuntime::getVMWrapper(const VMFunction &f) const
     JitRuntime::VMWrapperMap::Ptr p = functionWrappers_->readonlyThreadsafeLookup(&f);
     JS_ASSERT(p);
 
-    return p->value;
+    return p->value();
 }
 
 template <AllowGC allowGC>
diff --git a/js/src/jit/IonAnalysis.cpp b/js/src/jit/IonAnalysis.cpp
index 8d293a9c44d..5b148aa8f6c 100644
--- a/js/src/jit/IonAnalysis.cpp
+++ b/js/src/jit/IonAnalysis.cpp
@@ -1377,7 +1377,7 @@ FindDominatingBoundsCheck(BoundsCheckMap &checks, MBoundsCheck *check, size_t in
     // See the comment in ValueNumberer::findDominatingDef.
     HashNumber hash = BoundsCheckHashIgnoreOffset(check);
     BoundsCheckMap::Ptr p = checks.lookup(hash);
-    if (!p || index > p->value.validUntil) {
+    if (!p || index > p->value().validUntil) {
         // We didn't find a dominating bounds check.
         BoundsCheckInfo info;
         info.check = check;
@@ -1389,7 +1389,7 @@ FindDominatingBoundsCheck(BoundsCheckMap &checks, MBoundsCheck *check, size_t in
         return check;
     }
 
-    return p->value.check;
+    return p->value().check;
 }
 
 // Extract a linear sum from ins, if possible (otherwise giving the sum 'ins + 0').
diff --git a/js/src/jit/JitCompartment.h b/js/src/jit/JitCompartment.h
index b83cd8747ed..5ed17f32e8b 100644
--- a/js/src/jit/JitCompartment.h
+++ b/js/src/jit/JitCompartment.h
@@ -368,7 +368,7 @@ class JitCompartment
     IonCode *getStubCode(uint32_t key) {
         ICStubCodeMap::AddPtr p = stubCodes_->lookupForAdd(key);
         if (p)
-            return p->value;
+            return p->value();
         return nullptr;
     }
     bool putStubCode(uint32_t key, Handle<IonCode *> stubCode) {
diff --git a/js/src/jit/ValueNumbering.cpp b/js/src/jit/ValueNumbering.cpp
index 0fb3662101d..de967ee1545 100644
--- a/js/src/jit/ValueNumbering.cpp
+++ b/js/src/jit/ValueNumbering.cpp
@@ -35,14 +35,14 @@ ValueNumberer::lookupValue(MDefinition *ins)
 
     if (p) {
         // make sure this is in the correct group
-        setClass(ins, p->key);
+        setClass(ins, p->key());
     } else {
         if (!values.add(p, ins, ins->id()))
             return 0;
         breakClass(ins);
     }
 
-    return p->value;
+    return p->value();
 }
 
 MDefinition *
@@ -309,7 +309,7 @@ ValueNumberer::findDominatingDef(InstructionMap &defs, MDefinition *ins, size_t
     JS_ASSERT(ins->valueNumber() != 0);
     InstructionMap::Ptr p = defs.lookup(ins->valueNumber());
     MDefinition *dom;
-    if (!p || index > p->value.validUntil) {
+    if (!p || index > p->value().validUntil) {
         DominatingValue value;
         value.def = ins;
         // Since we are traversing the dominator tree in pre-order, when we
@@ -326,7 +326,7 @@ ValueNumberer::findDominatingDef(InstructionMap &defs, MDefinition *ins, size_t
 
         dom = ins;
     } else {
-        dom = p->value.def;
+        dom = p->value().def;
     }
 
     return dom;
diff --git a/js/src/jit/arm/Trampoline-arm.cpp b/js/src/jit/arm/Trampoline-arm.cpp
index 0b19d004c95..89a7b7b4188 100644
--- a/js/src/jit/arm/Trampoline-arm.cpp
+++ b/js/src/jit/arm/Trampoline-arm.cpp
@@ -660,7 +660,7 @@ JitRuntime::generateVMWrapper(JSContext *cx, const VMFunction &f)
     JS_ASSERT(functionWrappers_->initialized());
     VMWrapperMap::AddPtr p = functionWrappers_->lookupForAdd(&f);
     if (p)
-        return p->value;
+        return p->value();
 
     // Generate a separated code for the wrapper.
     MacroAssembler masm(cx);
diff --git a/js/src/jit/x64/MacroAssembler-x64.cpp b/js/src/jit/x64/MacroAssembler-x64.cpp
index cf95d88d7f5..4586b3f0167 100644
--- a/js/src/jit/x64/MacroAssembler-x64.cpp
+++ b/js/src/jit/x64/MacroAssembler-x64.cpp
@@ -28,7 +28,7 @@ MacroAssemblerX64::loadConstantDouble(double d, const FloatRegister &dest)
     }
     size_t doubleIndex;
     if (DoubleMap::AddPtr p = doubleMap_.lookupForAdd(d)) {
-        doubleIndex = p->value;
+        doubleIndex = p->value();
     } else {
         doubleIndex = doubles_.length();
         enoughMemory_ &= doubles_.append(Double(d));
@@ -62,7 +62,7 @@ MacroAssemblerX64::loadConstantFloat32(float f, const FloatRegister &dest)
     }
     size_t floatIndex;
     if (FloatMap::AddPtr p = floatMap_.lookupForAdd(f)) {
-        floatIndex = p->value;
+        floatIndex = p->value();
     } else {
         floatIndex = floats_.length();
         enoughMemory_ &= floats_.append(Float(f));
diff --git a/js/src/jit/x64/Trampoline-x64.cpp b/js/src/jit/x64/Trampoline-x64.cpp
index c73d4d31bdc..d41d42bea39 100644
--- a/js/src/jit/x64/Trampoline-x64.cpp
+++ b/js/src/jit/x64/Trampoline-x64.cpp
@@ -510,7 +510,7 @@ JitRuntime::generateVMWrapper(JSContext *cx, const VMFunction &f)
     JS_ASSERT(functionWrappers_->initialized());
     VMWrapperMap::AddPtr p = functionWrappers_->lookupForAdd(&f);
     if (p)
-        return p->value;
+        return p->value();
 
     // Generate a separated code for the wrapper.
     MacroAssembler masm;
diff --git a/js/src/jit/x86/MacroAssembler-x86.cpp b/js/src/jit/x86/MacroAssembler-x86.cpp
index 77b9a16ccf5..ace3e98d36a 100644
--- a/js/src/jit/x86/MacroAssembler-x86.cpp
+++ b/js/src/jit/x86/MacroAssembler-x86.cpp
@@ -29,7 +29,7 @@ MacroAssemblerX86::getDouble(double d)
     size_t doubleIndex;
     DoubleMap::AddPtr p = doubleMap_.lookupForAdd(d);
     if (p) {
-        doubleIndex = p->value;
+        doubleIndex = p->value();
     } else {
         doubleIndex = doubles_.length();
         enoughMemory_ &= doubles_.append(Double(d));
@@ -75,7 +75,7 @@ MacroAssemblerX86::getFloat(float f)
     size_t floatIndex;
     FloatMap::AddPtr p = floatMap_.lookupForAdd(f);
     if (p) {
-        floatIndex = p->value;
+        floatIndex = p->value();
     } else {
         floatIndex = floats_.length();
         enoughMemory_ &= floats_.append(Float(f));
diff --git a/js/src/jit/x86/Trampoline-x86.cpp b/js/src/jit/x86/Trampoline-x86.cpp
index 30f601835fe..c6de13cdd6a 100644
--- a/js/src/jit/x86/Trampoline-x86.cpp
+++ b/js/src/jit/x86/Trampoline-x86.cpp
@@ -545,7 +545,7 @@ JitRuntime::generateVMWrapper(JSContext *cx, const VMFunction &f)
     JS_ASSERT(functionWrappers_->initialized());
     VMWrapperMap::AddPtr p = functionWrappers_->lookupForAdd(&f);
     if (p)
-        return p->value;
+        return p->value();
 
     // Generate a separated code for the wrapper.
     MacroAssembler masm;
diff --git a/js/src/jsapi-tests/testHashTable.cpp b/js/src/jsapi-tests/testHashTable.cpp
index a20fd590abe..a335e62b4ba 100644
--- a/js/src/jsapi-tests/testHashTable.cpp
+++ b/js/src/jsapi-tests/testHashTable.cpp
@@ -61,15 +61,15 @@ MapsAreEqual(IntMap &am, IntMap &bm)
         fprintf(stderr, "A.count() == %u and B.count() == %u\n", am.count(), bm.count());
     }
     for (IntMap::Range r = am.all(); !r.empty(); r.popFront()) {
-        if (!bm.has(r.front().key)) {
+        if (!bm.has(r.front().key())) {
             equal = false;
-            fprintf(stderr, "B does not have %x which is in A\n", r.front().key);
+            fprintf(stderr, "B does not have %x which is in A\n", r.front().key());
         }
     }
     for (IntMap::Range r = bm.all(); !r.empty(); r.popFront()) {
-        if (!am.has(r.front().key)) {
+        if (!am.has(r.front().key())) {
             equal = false;
-            fprintf(stderr, "A does not have %x which is in B\n", r.front().key);
+            fprintf(stderr, "A does not have %x which is in B\n", r.front().key());
         }
     }
     return equal;
@@ -141,17 +141,17 @@ SlowRekey(IntMap *m) {
     tmp.init();
 
     for (IntMap::Range r = m->all(); !r.empty(); r.popFront()) {
-        if (NewKeyFunction::shouldBeRemoved(r.front().key))
+        if (NewKeyFunction::shouldBeRemoved(r.front().key()))
             continue;
-        uint32_t hi = NewKeyFunction::rekey(r.front().key);
+        uint32_t hi = NewKeyFunction::rekey(r.front().key());
         if (tmp.has(hi))
             return false;
-        tmp.putNew(hi, r.front().value);
+        tmp.putNew(hi, r.front().value());
     }
 
     m->clear();
     for (IntMap::Range r = tmp.all(); !r.empty(); r.popFront()) {
-        m->putNew(r.front().key, r.front().value);
+        m->putNew(r.front().key(), r.front().value());
     }
 
     return true;
@@ -193,8 +193,8 @@ BEGIN_TEST(testHashRekeyManual)
         CHECK(MapsAreEqual(am, bm));
 
         for (IntMap::Enum e(am); !e.empty(); e.popFront()) {
-            uint32_t tmp = LowToHigh::rekey(e.front().key);
-            if (tmp != e.front().key)
+            uint32_t tmp = LowToHigh::rekey(e.front().key());
+            if (tmp != e.front().key())
                 e.rekeyFront(tmp);
         }
         CHECK(SlowRekey<LowToHigh>(&bm));
@@ -243,11 +243,11 @@ BEGIN_TEST(testHashRekeyManualRemoval)
         CHECK(MapsAreEqual(am, bm));
 
         for (IntMap::Enum e(am); !e.empty(); e.popFront()) {
-            if (LowToHighWithRemoval::shouldBeRemoved(e.front().key)) {
+            if (LowToHighWithRemoval::shouldBeRemoved(e.front().key())) {
                 e.removeFront();
             } else {
-                uint32_t tmp = LowToHighWithRemoval::rekey(e.front().key);
-                if (tmp != e.front().key)
+                uint32_t tmp = LowToHighWithRemoval::rekey(e.front().key());
+                if (tmp != e.front().key())
                     e.rekeyFront(tmp);
             }
         }
diff --git a/js/src/jsapi.cpp b/js/src/jsapi.cpp
index 6b865e3bc48..913c7a7d0b3 100644
--- a/js/src/jsapi.cpp
+++ b/js/src/jsapi.cpp
@@ -1095,7 +1095,7 @@ JS_TransplantObject(JSContext *cx, HandleObject origobj, HandleObject target)
         // There might already be a wrapper for the original object in
         // the new compartment. If there is, we use its identity and swap
         // in the contents of |target|.
-        newIdentity = &p->value.toObject();
+        newIdentity = &p->value().toObject();
 
         // When we remove origv from the wrapper map, its wrapper, newIdentity,
         // must immediately cease to be a cross-compartment wrapper. Neuter it.
diff --git a/js/src/jscntxt.cpp b/js/src/jscntxt.cpp
index 86e6936efd6..dcbbaae079b 100644
--- a/js/src/jscntxt.cpp
+++ b/js/src/jscntxt.cpp
@@ -101,8 +101,8 @@ JSCompartment::sweepCallsiteClones()
 {
     if (callsiteClones.initialized()) {
         for (CallsiteCloneTable::Enum e(callsiteClones); !e.empty(); e.popFront()) {
-            CallsiteCloneKey key = e.front().key;
-            JSFunction *fun = e.front().value;
+            CallsiteCloneKey key = e.front().key();
+            JSFunction *fun = e.front().value();
             if (!IsScriptMarked(&key.script) || !IsObjectMarked(&fun))
                 e.removeFront();
         }
@@ -128,7 +128,7 @@ js::ExistingCloneFunctionAtCallsite(const CallsiteCloneTable &table, JSFunction
 
     CallsiteCloneTable::Ptr p = table.lookup(CallsiteCloneKey(fun, script, script->pcToOffset(pc)));
     if (p)
-        return p->value;
+        return p->value();
 
     return nullptr;
 }
diff --git a/js/src/jscompartment.cpp b/js/src/jscompartment.cpp
index c4995d89fce..a4132018c96 100644
--- a/js/src/jscompartment.cpp
+++ b/js/src/jscompartment.cpp
@@ -229,7 +229,7 @@ JSCompartment::wrap(JSContext *cx, JSString **strp)
     /* Check the cache. */
     RootedValue key(cx, StringValue(str));
     if (WrapperMap::Ptr p = crossCompartmentWrappers.lookup(key)) {
-        *strp = p->value.get().toString();
+        *strp = p->value().get().toString();
         return true;
     }
 
@@ -333,7 +333,7 @@ JSCompartment::wrap(JSContext *cx, MutableHandleObject obj, HandleObject existin
     /* If we already have a wrapper for this value, use it. */
     RootedValue key(cx, ObjectValue(*obj));
     if (WrapperMap::Ptr p = crossCompartmentWrappers.lookup(key)) {
-        obj.set(&p->value.get().toObject());
+        obj.set(&p->value().get().toObject());
         JS_ASSERT(obj->is<CrossCompartmentWrapperObject>());
         JS_ASSERT(obj->getParent() == global);
         return true;
@@ -449,8 +449,8 @@ JSCompartment::markCrossCompartmentWrappers(JSTracer *trc)
     JS_ASSERT(!zone()->isCollecting());
 
     for (WrapperMap::Enum e(crossCompartmentWrappers); !e.empty(); e.popFront()) {
-        Value v = e.front().value;
-        if (e.front().key.kind == CrossCompartmentKey::ObjectWrapper) {
+        Value v = e.front().value();
+        if (e.front().key().kind == CrossCompartmentKey::ObjectWrapper) {
             ProxyObject *wrapper = &v.toObject().as<ProxyObject>();
 
             /*
@@ -474,12 +474,12 @@ void
 JSCompartment::markAllCrossCompartmentWrappers(JSTracer *trc)
 {
     for (WrapperMap::Enum e(crossCompartmentWrappers); !e.empty(); e.popFront()) {
-        CrossCompartmentKey key = e.front().key;
+        CrossCompartmentKey key = e.front().key();
         MarkGCThingRoot(trc, (void **)&key.wrapped, "CrossCompartmentKey::wrapped");
         if (key.debugger)
             MarkObjectRoot(trc, &key.debugger, "CrossCompartmentKey::debugger");
-        MarkValueRoot(trc, e.front().value.unsafeGet(), "CrossCompartmentWrapper");
-        if (key.wrapped != e.front().key.wrapped || key.debugger != e.front().key.debugger)
+        MarkValueRoot(trc, e.front().value().unsafeGet(), "CrossCompartmentWrapper");
+        if (key.wrapped != e.front().key().wrapped || key.debugger != e.front().key().debugger)
             e.rekeyFront(key);
     }
 }
@@ -577,14 +577,16 @@ JSCompartment::sweepCrossCompartmentWrappers()
 
     /* Remove dead wrappers from the table. */
     for (WrapperMap::Enum e(crossCompartmentWrappers); !e.empty(); e.popFront()) {
-        CrossCompartmentKey key = e.front().key;
+        CrossCompartmentKey key = e.front().key();
         bool keyDying = IsCellAboutToBeFinalized(&key.wrapped);
-        bool valDying = IsValueAboutToBeFinalized(e.front().value.unsafeGet());
+        bool valDying = IsValueAboutToBeFinalized(e.front().value().unsafeGet());
         bool dbgDying = key.debugger && IsObjectAboutToBeFinalized(&key.debugger);
         if (keyDying || valDying || dbgDying) {
             JS_ASSERT(key.kind != CrossCompartmentKey::StringWrapper);
             e.removeFront();
-        } else if (key.wrapped != e.front().key.wrapped || key.debugger != e.front().key.debugger) {
+        } else if (key.wrapped != e.front().key().wrapped ||
+                   key.debugger != e.front().key().debugger)
+        {
             e.rekeyFront(key);
         }
     }
diff --git a/js/src/jscompartment.h b/js/src/jscompartment.h
index e358b3066e5..d6bd84004a3 100644
--- a/js/src/jscompartment.h
+++ b/js/src/jscompartment.h
@@ -610,11 +610,11 @@ struct WrapperValue
      * is in use, the AutoWrapper rooter will ensure the wrapper gets marked.
      */
     explicit WrapperValue(const WrapperMap::Ptr &ptr)
-      : value(*ptr->value.unsafeGet())
+      : value(*ptr->value().unsafeGet())
     {}
 
     explicit WrapperValue(const WrapperMap::Enum &e)
-      : value(*e.front().value.unsafeGet())
+      : value(*e.front().value().unsafeGet())
     {}
 
     Value &get() { return value; }
diff --git a/js/src/jscompartmentinlines.h b/js/src/jscompartmentinlines.h
index c2a6c5ca118..70cdfc72375 100644
--- a/js/src/jscompartmentinlines.h
+++ b/js/src/jscompartmentinlines.h
@@ -91,9 +91,9 @@ JSCompartment::wrap(JSContext *cx, JS::MutableHandleValue vp, JS::HandleObject e
     JS::RootedValue v(cx, vp);
     if (js::WrapperMap::Ptr p = crossCompartmentWrappers.lookup(v)) {
 #ifdef DEBUG
-        cacheResult = &p->value.get().toObject();
+        cacheResult = &p->value().get().toObject();
 #else
-        vp.set(p->value);
+        vp.set(p->value());
         return true;
 #endif
     }
diff --git a/js/src/jsfriendapi.cpp b/js/src/jsfriendapi.cpp
index db2d56cdbd4..1d3bdab16a2 100644
--- a/js/src/jsfriendapi.cpp
+++ b/js/src/jsfriendapi.cpp
@@ -660,7 +660,7 @@ js::VisitGrayWrapperTargets(Zone *zone, GCThingCallback callback, void *closure)
     JSRuntime *rt = zone->runtimeFromMainThread();
     for (CompartmentsInZoneIter comp(zone); !comp.done(); comp.next()) {
         for (JSCompartment::WrapperEnum e(comp); !e.empty(); e.popFront()) {
-            gc::Cell *thing = e.front().key.wrapped;
+            gc::Cell *thing = e.front().key().wrapped;
             if (!IsInsideNursery(rt, thing) && thing->isMarked(gc::GRAY))
                 callback(closure, thing);
         }
diff --git a/js/src/jsgc.cpp b/js/src/jsgc.cpp
index da695cfa899..2055eaae455 100644
--- a/js/src/jsgc.cpp
+++ b/js/src/jsgc.cpp
@@ -2881,7 +2881,7 @@ InCrossCompartmentMap(JSObject *src, Cell *dst, JSGCTraceKind dstKind)
     if (dstKind == JSTRACE_OBJECT) {
         Value key = ObjectValue(*static_cast<JSObject *>(dst));
         if (WrapperMap::Ptr p = srccomp->lookupWrapper(key)) {
-            if (*p->value.unsafeGet() == ObjectValue(*src))
+            if (*p->value().unsafeGet() == ObjectValue(*src))
                 return true;
         }
     }
@@ -2891,7 +2891,7 @@ InCrossCompartmentMap(JSObject *src, Cell *dst, JSGCTraceKind dstKind)
      * know the right hashtable key, so we have to iterate.
      */
     for (JSCompartment::WrapperEnum e(srccomp); !e.empty(); e.popFront()) {
-        if (e.front().key.wrapped == dst && ToMarkable(e.front().value) == src)
+        if (e.front().key().wrapped == dst && ToMarkable(e.front().value()) == src)
             return true;
     }
 
@@ -3124,7 +3124,7 @@ BeginMarkPhase(JSRuntime *rt)
     /* Set the maybeAlive flag based on cross-compartment edges. */
     for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
-            Cell *dst = e.front().key.wrapped;
+            Cell *dst = e.front().key().wrapped;
             dst->tenuredZone()->maybeAlive = true;
         }
     }
@@ -3252,7 +3252,7 @@ js::gc::MarkingValidator::~MarkingValidator()
         return;
 
     for (BitmapMap::Range r(map.all()); !r.empty(); r.popFront())
-        js_delete(r.front().value);
+        js_delete(r.front().value());
 }
 
 void
@@ -3358,7 +3358,7 @@ js::gc::MarkingValidator::nonIncrementalMark()
     for (GCChunkSet::Range r(runtime->gcChunkSet.all()); !r.empty(); r.popFront()) {
         Chunk *chunk = r.front();
         ChunkBitmap *bitmap = &chunk->bitmap;
-        ChunkBitmap *entry = map.lookup(chunk)->value;
+        ChunkBitmap *entry = map.lookup(chunk)->value();
         Swap(*entry, *bitmap);
     }
 
@@ -3390,7 +3390,7 @@ js::gc::MarkingValidator::validate()
         if (!ptr)
             continue;  /* Allocated after we did the non-incremental mark. */
 
-        ChunkBitmap *bitmap = ptr->value;
+        ChunkBitmap *bitmap = ptr->value();
         ChunkBitmap *incBitmap = &chunk->bitmap;
 
         for (size_t i = 0; i < ArenasPerChunk; i++) {
@@ -3482,7 +3482,7 @@ DropStringWrappers(JSRuntime *rt)
      */
     for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
-            if (e.front().key.kind == CrossCompartmentKey::StringWrapper)
+            if (e.front().key().kind == CrossCompartmentKey::StringWrapper)
                 e.removeFront();
         }
     }
@@ -3507,9 +3507,9 @@ void
 JSCompartment::findOutgoingEdges(ComponentFinder<JS::Zone> &finder)
 {
     for (js::WrapperMap::Enum e(crossCompartmentWrappers); !e.empty(); e.popFront()) {
-        CrossCompartmentKey::Kind kind = e.front().key.kind;
+        CrossCompartmentKey::Kind kind = e.front().key().kind;
         JS_ASSERT(kind != CrossCompartmentKey::StringWrapper);
-        Cell *other = e.front().key.wrapped;
+        Cell *other = e.front().key().wrapped;
         if (kind == CrossCompartmentKey::ObjectWrapper) {
             /*
              * Add edge to wrapped object compartment if wrapped object is not
@@ -4033,8 +4033,8 @@ BeginSweepPhase(JSRuntime *rt, bool lastGC)
     for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
         JS_ASSERT(!c->gcIncomingGrayPointers);
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
-            if (e.front().key.kind != CrossCompartmentKey::StringWrapper)
-                AssertNotOnGrayList(&e.front().value.get().toObject());
+            if (e.front().key().kind != CrossCompartmentKey::StringWrapper)
+                AssertNotOnGrayList(&e.front().value().get().toObject());
         }
     }
 #endif
@@ -4256,8 +4256,8 @@ EndSweepPhase(JSRuntime *rt, JSGCInvocationKind gckind, bool lastGC)
         JS_ASSERT(!c->gcLiveArrayBuffers);
 
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
-            if (e.front().key.kind != CrossCompartmentKey::StringWrapper)
-                AssertNotOnGrayList(&e.front().value.get().toObject());
+            if (e.front().key().kind != CrossCompartmentKey::StringWrapper)
+                AssertNotOnGrayList(&e.front().value().get().toObject());
         }
     }
 #endif
diff --git a/js/src/jsinfer.cpp b/js/src/jsinfer.cpp
index 6b0d072d916..ae560d58286 100644
--- a/js/src/jsinfer.cpp
+++ b/js/src/jsinfer.cpp
@@ -1822,7 +1822,7 @@ TypeCompartment::addAllocationSiteTypeObject(JSContext *cx, AllocationSiteKey ke
 
         AllocationSiteTable::Ptr p = cx->compartment()->types.allocationSiteTable->lookup(nkey);
         if (p)
-            res = p->value;
+            res = p->value();
     }
 
     if (!res) {
@@ -2303,7 +2303,7 @@ TypeCompartment::setTypeToHomogenousArray(ExclusiveContext *cx,
     ArrayTableKey key(elementType, obj->getProto());
     DependentAddPtr<ArrayTypeTable> p(cx, *arrayTypeTable, key);
     if (p) {
-        obj->setType(p->value);
+        obj->setType(p->value());
     } else {
         /* Make a new type to use for future arrays with the same elements. */
         RootedObject objProto(cx, obj->getProto());
@@ -2492,11 +2492,11 @@ TypeCompartment::fixObjectType(ExclusiveContext *cx, JSObject *obj)
     ObjectTypeTable::AddPtr p = objectTypeTable->lookupForAdd(lookup);
 
     if (p) {
-        JS_ASSERT(obj->getProto() == p->value.object->proto);
-        JS_ASSERT(obj->lastProperty() == p->value.shape);
+        JS_ASSERT(obj->getProto() == p->value().object->proto);
+        JS_ASSERT(obj->lastProperty() == p->value().shape);
 
-        UpdateObjectTableEntryTypes(cx, p->value, properties.begin(), properties.length());
-        obj->setType(p->value.object);
+        UpdateObjectTableEntryTypes(cx, p->value(), properties.begin(), properties.length());
+        obj->setType(p->value().object);
         return;
     }
 
@@ -2595,20 +2595,20 @@ TypeCompartment::newTypedObject(JSContext *cx, IdValuePair *properties, size_t n
         cx->clearPendingException();
         return nullptr;
     }
-    JS_ASSERT(obj->getProto() == p->value.object->proto);
+    JS_ASSERT(obj->getProto() == p->value().object->proto);
 
-    RootedShape shape(cx, p->value.shape);
+    RootedShape shape(cx, p->value().shape);
     if (!JSObject::setLastProperty(cx, obj, shape)) {
         cx->clearPendingException();
         return nullptr;
     }
 
-    UpdateObjectTableEntryTypes(cx, p->value, properties, nproperties);
+    UpdateObjectTableEntryTypes(cx, p->value(), properties, nproperties);
 
     for (size_t i = 0; i < nproperties; i++)
         obj->setSlot(i, properties[i].value);
 
-    obj->setType(p->value.object);
+    obj->setType(p->value().object);
     return obj;
 }
 
@@ -4026,7 +4026,7 @@ TypeCompartment::sweep(FreeOp *fop)
 
     if (arrayTypeTable) {
         for (ArrayTypeTable::Enum e(*arrayTypeTable); !e.empty(); e.popFront()) {
-            const ArrayTableKey &key = e.front().key;
+            const ArrayTableKey &key = e.front().key();
             JS_ASSERT(key.type.isUnknown() || !key.type.isSingleObject());
 
             bool remove = false;
@@ -4036,7 +4036,7 @@ TypeCompartment::sweep(FreeOp *fop)
                 if (IsTypeObjectAboutToBeFinalized(&typeObject))
                     remove = true;
             }
-            if (IsTypeObjectAboutToBeFinalized(e.front().value.unsafeGet()))
+            if (IsTypeObjectAboutToBeFinalized(e.front().value().unsafeGet()))
                 remove = true;
 
             if (remove) {
@@ -4052,8 +4052,8 @@ TypeCompartment::sweep(FreeOp *fop)
 
     if (objectTypeTable) {
         for (ObjectTypeTable::Enum e(*objectTypeTable); !e.empty(); e.popFront()) {
-            const ObjectTableKey &key = e.front().key;
-            ObjectTableEntry &entry = e.front().value;
+            const ObjectTableKey &key = e.front().key();
+            ObjectTableEntry &entry = e.front().value();
 
             bool remove = false;
             if (IsTypeObjectAboutToBeFinalized(entry.object.unsafeGet()))
@@ -4088,12 +4088,12 @@ TypeCompartment::sweep(FreeOp *fop)
 
     if (allocationSiteTable) {
         for (AllocationSiteTable::Enum e(*allocationSiteTable); !e.empty(); e.popFront()) {
-            AllocationSiteKey key = e.front().key;
+            AllocationSiteKey key = e.front().key();
             bool keyDying = IsScriptAboutToBeFinalized(&key.script);
-            bool valDying = IsTypeObjectAboutToBeFinalized(e.front().value.unsafeGet());
+            bool valDying = IsTypeObjectAboutToBeFinalized(e.front().value().unsafeGet());
             if (keyDying || valDying)
                 e.removeFront();
-            else if (key.script != e.front().key.script)
+            else if (key.script != e.front().key().script)
                 e.rekeyFront(key);
         }
     }
@@ -4118,8 +4118,8 @@ TypeCompartment::sweepShapes(FreeOp *fop)
      */
     if (objectTypeTable) {
         for (ObjectTypeTable::Enum e(*objectTypeTable); !e.empty(); e.popFront()) {
-            const ObjectTableKey &key = e.front().key;
-            ObjectTableEntry &entry = e.front().value;
+            const ObjectTableKey &key = e.front().key();
+            ObjectTableEntry &entry = e.front().value();
 
             if (IsShapeAboutToBeFinalized(entry.shape.unsafeGet())) {
                 fop->free_(key.properties);
@@ -4233,8 +4233,8 @@ TypeCompartment::addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf,
              !e.empty();
              e.popFront())
         {
-            const ObjectTableKey &key = e.front().key;
-            const ObjectTableEntry &value = e.front().value;
+            const ObjectTableKey &key = e.front().key();
+            const ObjectTableEntry &value = e.front().value();
 
             /* key.ids and values.types have the same length. */
             *objectTypeTables += mallocSizeOf(key.properties) + mallocSizeOf(value.types);
diff --git a/js/src/jsinferinlines.h b/js/src/jsinferinlines.h
index 607b7c5c898..992abd5a960 100644
--- a/js/src/jsinferinlines.h
+++ b/js/src/jsinferinlines.h
@@ -721,7 +721,7 @@ TypeScript::InitObject(JSContext *cx, JSScript *script, jsbytecode *pc, JSProtoK
     AllocationSiteTable::Ptr p = cx->compartment()->types.allocationSiteTable->lookup(key);
 
     if (p)
-        return p->value;
+        return p->value();
     return cx->compartment()->types.addAllocationSiteTypeObject(cx, key);
 }
 
diff --git a/js/src/jsproxy.cpp b/js/src/jsproxy.cpp
index 3b1f3de8b35..89345e8b62e 100644
--- a/js/src/jsproxy.cpp
+++ b/js/src/jsproxy.cpp
@@ -3008,7 +3008,7 @@ ProxyObject::trace(JSTracer *trc, JSObject *obj)
              */
             Value key = ObjectValue(*referent);
             WrapperMap::Ptr p = proxy->compartment()->lookupWrapper(key);
-            JS_ASSERT(*p->value.unsafeGet() == ObjectValue(*proxy));
+            JS_ASSERT(*p->value().unsafeGet() == ObjectValue(*proxy));
         }
     }
 #endif
diff --git a/js/src/jsscript.cpp b/js/src/jsscript.cpp
index dd717dad9b3..40c18b08964 100644
--- a/js/src/jsscript.cpp
+++ b/js/src/jsscript.cpp
@@ -912,30 +912,30 @@ js::PCCounts
 JSScript::getPCCounts(jsbytecode *pc) {
     JS_ASSERT(containsPC(pc));
     ScriptCountsMap::Ptr p = GetScriptCountsMapEntry(this);
-    return p->value.pcCountsVector[pcToOffset(pc)];
+    return p->value().pcCountsVector[pcToOffset(pc)];
 }
 
 void
 JSScript::addIonCounts(jit::IonScriptCounts *ionCounts)
 {
     ScriptCountsMap::Ptr p = GetScriptCountsMapEntry(this);
-    if (p->value.ionCounts)
-        ionCounts->setPrevious(p->value.ionCounts);
-    p->value.ionCounts = ionCounts;
+    if (p->value().ionCounts)
+        ionCounts->setPrevious(p->value().ionCounts);
+    p->value().ionCounts = ionCounts;
 }
 
 jit::IonScriptCounts *
 JSScript::getIonCounts()
 {
     ScriptCountsMap::Ptr p = GetScriptCountsMapEntry(this);
-    return p->value.ionCounts;
+    return p->value().ionCounts;
 }
 
 ScriptCounts
 JSScript::releaseScriptCounts()
 {
     ScriptCountsMap::Ptr p = GetScriptCountsMapEntry(this);
-    ScriptCounts counts = p->value;
+    ScriptCounts counts = p->value();
     compartment()->scriptCountsMap->remove(p);
     hasScriptCounts = false;
     return counts;
@@ -1082,7 +1082,7 @@ SourceDataCache::lookup(ScriptSource *ss, const AutoSuppressPurge &asp)
     if (!map_)
         return nullptr;
     if (Map::Ptr p = map_->lookup(ss))
-        return p->value;
+        return p->value();
     return nullptr;
 }
 
@@ -1113,7 +1113,7 @@ SourceDataCache::purge()
         return;
 
     for (Map::Range r = map_->all(); !r.empty(); r.popFront())
-        js_delete(const_cast<jschar*>(r.front().value));
+        js_delete(const_cast<jschar*>(r.front().value()));
 
     js_delete(map_);
     map_ = nullptr;
@@ -2164,7 +2164,7 @@ js::GetSrcNote(GSNCache &cache, JSScript *script, jsbytecode *pc)
     if (cache.code == script->code()) {
         JS_ASSERT(cache.map.initialized());
         GSNCache::Map::Ptr p = cache.map.lookup(pc);
-        return p ? p->value : nullptr;
+        return p ? p->value() : nullptr;
     }
 
     size_t offset = 0;
@@ -2591,7 +2591,7 @@ JSScript::debugScript()
     JS_ASSERT(map);
     DebugScriptMap::Ptr p = map->lookup(this);
     JS_ASSERT(p);
-    return p->value;
+    return p->value();
 }
 
 DebugScript *
@@ -2602,7 +2602,7 @@ JSScript::releaseDebugScript()
     JS_ASSERT(map);
     DebugScriptMap::Ptr p = map->lookup(this);
     JS_ASSERT(p);
-    DebugScript *debug = p->value;
+    DebugScript *debug = p->value();
     map->remove(p);
     hasDebugScript = false;
     return debug;
diff --git a/js/src/jswatchpoint.cpp b/js/src/jswatchpoint.cpp
index 0a3d42d9a68..3488dac5af0 100644
--- a/js/src/jswatchpoint.cpp
+++ b/js/src/jswatchpoint.cpp
@@ -35,16 +35,17 @@ class AutoEntryHolder {
 
   public:
     AutoEntryHolder(JSContext *cx, Map &map, Map::Ptr p)
-        : map(map), p(p), gen(map.generation()), obj(cx, p->key.object), id(cx, p->key.id) {
-        JS_ASSERT(!p->value.held);
-        p->value.held = true;
+      : map(map), p(p), gen(map.generation()), obj(cx, p->key().object), id(cx, p->key().id)
+    {
+        JS_ASSERT(!p->value().held);
+        p->value().held = true;
     }
 
     ~AutoEntryHolder() {
         if (gen != map.generation())
             p = map.lookup(WatchKey(obj, id));
         if (p)
-            p->value.held = false;
+            p->value().held = false;
     }
 };
 
@@ -84,12 +85,12 @@ WatchpointMap::unwatch(JSObject *obj, jsid id,
 {
     if (Map::Ptr p = map.lookup(WatchKey(obj, id))) {
         if (handlerp)
-            *handlerp = p->value.handler;
+            *handlerp = p->value().handler;
         if (closurep) {
             // Read barrier to prevent an incorrectly gray closure from escaping the
             // watchpoint. See the comment before UnmarkGrayChildren in gc/Marking.cpp
-            JS::ExposeGCThingToActiveJS(p->value.closure, JSTRACE_OBJECT);
-            *closurep = p->value.closure;
+            JS::ExposeGCThingToActiveJS(p->value().closure, JSTRACE_OBJECT);
+            *closurep = p->value().closure;
         }
         map.remove(p);
     }
@@ -100,7 +101,7 @@ WatchpointMap::unwatchObject(JSObject *obj)
 {
     for (Map::Enum e(map); !e.empty(); e.popFront()) {
         Map::Entry &entry = e.front();
-        if (entry.key.object == obj)
+        if (entry.key().object == obj)
             e.removeFront();
     }
 }
@@ -115,14 +116,14 @@ bool
 WatchpointMap::triggerWatchpoint(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
 {
     Map::Ptr p = map.lookup(WatchKey(obj, id));
-    if (!p || p->value.held)
+    if (!p || p->value().held)
         return true;
 
     AutoEntryHolder holder(cx, map, p);
 
     /* Copy the entry, since GC would invalidate p. */
-    JSWatchPointHandler handler = p->value.handler;
-    RootedObject closure(cx, p->value.closure);
+    JSWatchPointHandler handler = p->value().handler;
+    RootedObject closure(cx, p->value().closure);
 
     /* Determine the property's old value. */
     Value old;
@@ -156,27 +157,28 @@ WatchpointMap::markIteratively(JSTracer *trc)
     bool marked = false;
     for (Map::Enum e(map); !e.empty(); e.popFront()) {
         Map::Entry &entry = e.front();
-        JSObject *priorKeyObj = entry.key.object;
-        jsid priorKeyId(entry.key.id.get());
-        bool objectIsLive = IsObjectMarked(const_cast<EncapsulatedPtrObject *>(&entry.key.object));
-        if (objectIsLive || entry.value.held) {
+        JSObject *priorKeyObj = entry.key().object;
+        jsid priorKeyId(entry.key().id.get());
+        bool objectIsLive =
+            IsObjectMarked(const_cast<EncapsulatedPtrObject *>(&entry.key().object));
+        if (objectIsLive || entry.value().held) {
             if (!objectIsLive) {
-                MarkObject(trc, const_cast<EncapsulatedPtrObject *>(&entry.key.object),
+                MarkObject(trc, const_cast<EncapsulatedPtrObject *>(&entry.key().object),
                            "held Watchpoint object");
                 marked = true;
             }
 
             JS_ASSERT(JSID_IS_STRING(priorKeyId) || JSID_IS_INT(priorKeyId));
-            MarkId(trc, const_cast<EncapsulatedId *>(&entry.key.id), "WatchKey::id");
+            MarkId(trc, const_cast<EncapsulatedId *>(&entry.key().id), "WatchKey::id");
 
-            if (entry.value.closure && !IsObjectMarked(&entry.value.closure)) {
-                MarkObject(trc, &entry.value.closure, "Watchpoint::closure");
+            if (entry.value().closure && !IsObjectMarked(&entry.value().closure)) {
+                MarkObject(trc, &entry.value().closure, "Watchpoint::closure");
                 marked = true;
             }
 
             /* We will sweep this entry in sweepAll if !objectIsLive. */
-            if (priorKeyObj != entry.key.object || priorKeyId != entry.key.id)
-                e.rekeyFront(WatchKey(entry.key.object, entry.key.id));
+            if (priorKeyObj != entry.key().object || priorKeyId != entry.key().id)
+                e.rekeyFront(WatchKey(entry.key().object, entry.key().id));
         }
     }
     return marked;
@@ -187,14 +189,14 @@ WatchpointMap::markAll(JSTracer *trc)
 {
     for (Map::Enum e(map); !e.empty(); e.popFront()) {
         Map::Entry &entry = e.front();
-        WatchKey key = entry.key;
+        WatchKey key = entry.key();
         WatchKey prior = key;
         JS_ASSERT(JSID_IS_STRING(prior.id) || JSID_IS_INT(prior.id));
 
         MarkObject(trc, const_cast<EncapsulatedPtrObject *>(&key.object),
                    "held Watchpoint object");
         MarkId(trc, const_cast<EncapsulatedId *>(&key.id), "WatchKey::id");
-        MarkObject(trc, &entry.value.closure, "Watchpoint::closure");
+        MarkObject(trc, &entry.value().closure, "Watchpoint::closure");
 
         if (prior.object != key.object || prior.id != key.id)
             e.rekeyFront(key);
@@ -215,12 +217,12 @@ WatchpointMap::sweep()
 {
     for (Map::Enum e(map); !e.empty(); e.popFront()) {
         Map::Entry &entry = e.front();
-        JSObject *obj(entry.key.object);
+        JSObject *obj(entry.key().object);
         if (IsObjectAboutToBeFinalized(&obj)) {
-            JS_ASSERT(!entry.value.held);
+            JS_ASSERT(!entry.value().held);
             e.removeFront();
-        } else if (obj != entry.key.object) {
-            e.rekeyFront(WatchKey(obj, entry.key.id));
+        } else if (obj != entry.key().object) {
+            e.rekeyFront(WatchKey(obj, entry.key().id));
         }
     }
 }
@@ -241,7 +243,7 @@ WatchpointMap::trace(WeakMapTracer *trc)
     for (Map::Range r = map.all(); !r.empty(); r.popFront()) {
         Map::Entry &entry = r.front();
         trc->callback(trc, nullptr,
-                      entry.key.object.get(), JSTRACE_OBJECT,
-                      entry.value.closure.get(), JSTRACE_OBJECT);
+                      entry.key().object.get(), JSTRACE_OBJECT,
+                      entry.value().closure.get(), JSTRACE_OBJECT);
     }
 }
diff --git a/js/src/jsweakcache.h b/js/src/jsweakcache.h
index 93629acd252..08637d3edec 100644
--- a/js/src/jsweakcache.h
+++ b/js/src/jsweakcache.h
@@ -89,7 +89,7 @@ class WeakValueCache : public HashMap<Key, Value, HashPolicy, AllocPolicy>
     void sweep(FreeOp *fop) {
         // Remove all entries whose values remain unmarked.
         for (Enum e(*this); !e.empty(); e.popFront()) {
-            if (gc::IsAboutToBeFinalized(e.front().value))
+            if (gc::IsAboutToBeFinalized(e.front().value()))
                 e.removeFront();
         }
 
@@ -97,7 +97,7 @@ class WeakValueCache : public HashMap<Key, Value, HashPolicy, AllocPolicy>
         // Once we've swept, all remaining edges should stay within the
         // known-live part of the graph.
         for (Range r = Base::all(); !r.empty(); r.popFront())
-            JS_ASSERT(!gc::IsAboutToBeFinalized(r.front().value));
+            JS_ASSERT(!gc::IsAboutToBeFinalized(r.front().value()));
 #endif
     }
 };
diff --git a/js/src/jsweakmap.cpp b/js/src/jsweakmap.cpp
index 3888f2d8976..9a052c3f611 100644
--- a/js/src/jsweakmap.cpp
+++ b/js/src/jsweakmap.cpp
@@ -200,9 +200,9 @@ WeakMap_get_impl(JSContext *cx, CallArgs args)
         if (ObjectValueMap::Ptr ptr = map->lookup(key)) {
             // Read barrier to prevent an incorrectly gray value from escaping the
             // weak map. See the comment before UnmarkGrayChildren in gc/Marking.cpp
-            ExposeValueToActiveJS(ptr->value.get());
+            ExposeValueToActiveJS(ptr->value().get());
 
-            args.rval().set(ptr->value);
+            args.rval().set(ptr->value());
             return true;
         }
     }
@@ -357,7 +357,7 @@ JS_NondeterministicGetWeakMapKeys(JSContext *cx, JSObject *objArg, JSObject **re
         // Prevent GC from mutating the weakmap while iterating.
         gc::AutoSuppressGC suppress(cx);
         for (ObjectValueMap::Base::Range r = map->all(); !r.empty(); r.popFront()) {
-            RootedObject key(cx, r.front().key);
+            RootedObject key(cx, r.front().key());
             if (!cx->compartment()->wrap(cx, &key))
                 return false;
             if (!js_NewbornArrayPush(cx, arr, ObjectValue(*key)))
diff --git a/js/src/jsweakmap.h b/js/src/jsweakmap.h
index fed7c05ed49..4b4c829beee 100644
--- a/js/src/jsweakmap.h
+++ b/js/src/jsweakmap.h
@@ -148,16 +148,16 @@ class WeakMap : public HashMap<Key, Value, HashPolicy, RuntimeAllocPolicy>, publ
 
     void nonMarkingTraceKeys(JSTracer *trc) {
         for (Enum e(*this); !e.empty(); e.popFront()) {
-            Key key(e.front().key);
+            Key key(e.front().key());
             gc::Mark(trc, &key, "WeakMap entry key");
-            if (key != e.front().key)
+            if (key != e.front().key())
                 entryMoved(e, key);
         }
     }
 
     void nonMarkingTraceValues(JSTracer *trc) {
         for (Range r = Base::all(); !r.empty(); r.popFront())
-            gc::Mark(trc, &r.front().value, "WeakMap entry value");
+            gc::Mark(trc, &r.front().value(), "WeakMap entry value");
     }
 
     bool keyNeedsMark(JSObject *key) {
@@ -181,17 +181,17 @@ class WeakMap : public HashMap<Key, Value, HashPolicy, RuntimeAllocPolicy>, publ
         bool markedAny = false;
         for (Enum e(*this); !e.empty(); e.popFront()) {
             /* If the entry is live, ensure its key and value are marked. */
-            Key key(e.front().key);
+            Key key(e.front().key());
             if (gc::IsMarked(const_cast<Key *>(&key))) {
-                if (markValue(trc, &e.front().value))
+                if (markValue(trc, &e.front().value()))
                     markedAny = true;
-                if (e.front().key != key)
+                if (e.front().key() != key)
                     entryMoved(e, key);
             } else if (keyNeedsMark(key)) {
-                gc::Mark(trc, const_cast<Key *>(&key), "proxy-preserved WeakMap entry key");
-                if (e.front().key != key)
+                gc::Mark(trc, &key, "proxy-preserved WeakMap entry key");
+                if (e.front().key() != key)
                     entryMoved(e, key);
-                gc::Mark(trc, &e.front().value, "WeakMap entry value");
+                gc::Mark(trc, &e.front().value(), "WeakMap entry value");
                 markedAny = true;
             }
             key.unsafeSet(nullptr);
@@ -202,10 +202,10 @@ class WeakMap : public HashMap<Key, Value, HashPolicy, RuntimeAllocPolicy>, publ
     void sweep() {
         /* Remove all entries whose keys remain unmarked. */
         for (Enum e(*this); !e.empty(); e.popFront()) {
-            Key k(e.front().key);
+            Key k(e.front().key());
             if (gc::IsAboutToBeFinalized(&k))
                 e.removeFront();
-            else if (k != e.front().key)
+            else if (k != e.front().key())
                 entryMoved(e, k);
         }
         /*
@@ -218,12 +218,12 @@ class WeakMap : public HashMap<Key, Value, HashPolicy, RuntimeAllocPolicy>, publ
     /* memberOf can be nullptr, which means that the map is not part of a JSObject. */
     void traceMappings(WeakMapTracer *tracer) {
         for (Range r = Base::all(); !r.empty(); r.popFront()) {
-            gc::Cell *key = gc::ToMarkable(r.front().key);
-            gc::Cell *value = gc::ToMarkable(r.front().value);
+            gc::Cell *key = gc::ToMarkable(r.front().key());
+            gc::Cell *value = gc::ToMarkable(r.front().value());
             if (key && value) {
                 tracer->callback(tracer, memberOf,
-                                 key, gc::TraceKind(r.front().key),
-                                 value, gc::TraceKind(r.front().value));
+                                 key, gc::TraceKind(r.front().key()),
+                                 value, gc::TraceKind(r.front().value()));
             }
         }
     }
@@ -242,10 +242,10 @@ protected:
     void assertEntriesNotAboutToBeFinalized() {
 #if DEBUG
         for (Range r = Base::all(); !r.empty(); r.popFront()) {
-            Key k(r.front().key);
+            Key k(r.front().key());
             JS_ASSERT(!gc::IsAboutToBeFinalized(&k));
-            JS_ASSERT(!gc::IsAboutToBeFinalized(&r.front().value));
-            JS_ASSERT(k == r.front().key);
+            JS_ASSERT(!gc::IsAboutToBeFinalized(&r.front().value()));
+            JS_ASSERT(k == r.front().key());
         }
 #endif
     }
diff --git a/js/src/jswrapper.cpp b/js/src/jswrapper.cpp
index 72f120e9f06..53e29f60bd4 100644
--- a/js/src/jswrapper.cpp
+++ b/js/src/jswrapper.cpp
@@ -893,7 +893,7 @@ js::NukeCrossCompartmentWrappers(JSContext* cx,
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
             // Some cross-compartment wrappers are for strings.  We're not
             // interested in those.
-            const CrossCompartmentKey &k = e.front().key;
+            const CrossCompartmentKey &k = e.front().key();
             if (k.kind != CrossCompartmentKey::ObjectWrapper)
                 continue;
 
@@ -941,7 +941,7 @@ js::RemapWrapper(JSContext *cx, JSObject *wobjArg, JSObject *newTargetArg)
     // The old value should still be in the cross-compartment wrapper map, and
     // the lookup should return wobj.
     WrapperMap::Ptr p = wcompartment->lookupWrapper(origv);
-    JS_ASSERT(&p->value.unsafeGet()->toObject() == wobj);
+    JS_ASSERT(&p->value().unsafeGet()->toObject() == wobj);
     wcompartment->removeWrapper(p);
 
     // When we remove origv from the wrapper map, its wrapper, wobj, must
@@ -1025,7 +1025,7 @@ js::RecomputeWrappers(JSContext *cx, const CompartmentFilter &sourceFilter,
         // Iterate over the wrappers, filtering appropriately.
         for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
             // Filter out non-objects.
-            const CrossCompartmentKey &k = e.front().key;
+            const CrossCompartmentKey &k = e.front().key();
             if (k.kind != CrossCompartmentKey::ObjectWrapper)
                 continue;
 
diff --git a/js/src/shell/jsheaptools.cpp b/js/src/shell/jsheaptools.cpp
index ded94ab193b..3bdb618a435 100644
--- a/js/src/shell/jsheaptools.cpp
+++ b/js/src/shell/jsheaptools.cpp
@@ -246,8 +246,8 @@ class HeapReverser : public JSTracer, public JS::CustomAutoRooter
         if (!map.initialized())
             return;
         for (Map::Enum e(map); !e.empty(); e.popFront()) {
-            gc::MarkGCThingRoot(trc, const_cast<void **>(&e.front().key), "HeapReverser::map::key");
-            e.front().value.trace(trc);
+            gc::MarkGCThingRoot(trc, const_cast<void **>(&e.front().key()), "HeapReverser::map::key");
+            e.front().value().trace(trc);
         }
         for (Child *c = work.begin(); c != work.end(); ++c)
             gc::MarkGCThingRoot(trc, &c->cell, "HeapReverser::Child");
@@ -281,7 +281,7 @@ HeapReverser::traverseEdge(void *cell, JSGCTraceKind kind)
     }
 
     /* Add this edge to the reversed map. */
-    return a->value.incoming.append(Move(e));
+    return a->value().incoming.append(Move(e));
 }
 
 bool
@@ -427,7 +427,7 @@ ReferenceFinder::visit(void *cell, Path *path)
 
     HeapReverser::Map::Ptr p = reverser.map.lookup(cell);
     JS_ASSERT(p);
-    HeapReverser::Node *node = &p->value;
+    HeapReverser::Node *node = &p->value();
 
     /* Is |cell| a representable cell, reached via a non-empty path? */
     if (path != nullptr) {
diff --git a/js/src/vm/Debugger.cpp b/js/src/vm/Debugger.cpp
index 9711155e2c6..c426d29fa0d 100644
--- a/js/src/vm/Debugger.cpp
+++ b/js/src/vm/Debugger.cpp
@@ -211,7 +211,7 @@ class Debugger::FrameRange
 
     JSObject *frontFrame() const {
         JS_ASSERT(!empty());
-        return entry->value;
+        return entry->value();
     }
 
     Debugger *frontDebugger() const {
@@ -468,7 +468,7 @@ Debugger::getScriptFrame(JSContext *cx, AbstractFramePtr frame, MutableHandleVal
             return false;
         }
     }
-    vp.setObject(*p->value);
+    vp.setObject(*p->value());
     return true;
 }
 
@@ -501,7 +501,7 @@ Debugger::hasAnyLiveHooks() const
     }
 
     for (FrameMap::Range r = frames.all(); !r.empty(); r.popFront()) {
-        JSObject *frameObj = r.front().value;
+        JSObject *frameObj = r.front().value();
         if (!frameObj->getReservedSlot(JSSLOT_DEBUGFRAME_ONSTEP_HANDLER).isUndefined() ||
             !frameObj->getReservedSlot(JSSLOT_DEBUGFRAME_ONPOP_HANDLER).isUndefined())
             return true;
@@ -674,7 +674,7 @@ Debugger::wrapEnvironment(JSContext *cx, Handle<Env*> env, MutableHandleValue rv
     JSObject *envobj;
     DependentAddPtr<ObjectWeakMap> p(cx, environments, env);
     if (p) {
-        envobj = p->value;
+        envobj = p->value();
     } else {
         /* Create a new Debugger.Environment for env. */
         JSObject *proto = &object->getReservedSlot(JSSLOT_DEBUG_ENV_PROTO).toObject();
@@ -715,7 +715,7 @@ Debugger::wrapDebuggeeValue(JSContext *cx, MutableHandleValue vp)
 
         DependentAddPtr<ObjectWeakMap> p(cx, objects, obj);
         if (p) {
-            vp.setObject(*p->value);
+            vp.setObject(*p->value());
         } else {
             /* Create a new Debugger.Object for obj. */
             JSObject *proto = &object->getReservedSlot(JSSLOT_DEBUG_OBJECT_PROTO).toObject();
@@ -1267,8 +1267,8 @@ Debugger::onSingleStep(JSContext *cx, MutableHandleValue vp)
             for (Debugger **p = debuggers->begin(); p != debuggers->end(); p++) {
                 Debugger *dbg = *p;
                 for (FrameMap::Range r = dbg->frames.all(); !r.empty(); r.popFront()) {
-                    AbstractFramePtr frame = r.front().key;
-                    JSObject *frameobj = r.front().value;
+                    AbstractFramePtr frame = r.front().key();
+                    JSObject *frameobj = r.front().value();
                     if (frame.script() == trappingScript &&
                         !frameobj->getReservedSlot(JSSLOT_DEBUGFRAME_ONSTEP_HANDLER).isUndefined())
                     {
@@ -1594,7 +1594,7 @@ Debugger::trace(JSTracer *trc)
      * frames.)
      */
     for (FrameMap::Range r = frames.all(); !r.empty(); r.popFront()) {
-        RelocatablePtrObject &frameobj = r.front().value;
+        RelocatablePtrObject &frameobj = r.front().value();
         JS_ASSERT(frameobj->getPrivate());
         MarkObject(trc, &frameobj, "live Debugger.Frame");
     }
@@ -2272,9 +2272,9 @@ Debugger::removeDebuggeeGlobal(FreeOp *fop, GlobalObject *global,
      * which slowPathOnLeaveFrame would have to examine.
      */
     for (FrameMap::Enum e(frames); !e.empty(); e.popFront()) {
-        AbstractFramePtr frame = e.front().key;
+        AbstractFramePtr frame = e.front().key();
         if (&frame.script()->global() == global) {
-            DebuggerFrame_freeScriptFrameIterData(fop, e.front().value);
+            DebuggerFrame_freeScriptFrameIterData(fop, e.front().value());
             e.removeFront();
         }
     }
@@ -2454,7 +2454,7 @@ class Debugger::ScriptQuery {
             for (CompartmentToScriptMap::Range r = innermostForCompartment.all();
                  !r.empty();
                  r.popFront()) {
-                if (!v->append(r.front().value)) {
+                if (!v->append(r.front().value())) {
                     js_ReportOutOfMemory(cx);
                     return false;
                 }
@@ -2599,9 +2599,9 @@ class Debugger::ScriptQuery {
             CompartmentToScriptMap::AddPtr p = innermostForCompartment.lookupForAdd(compartment);
             if (p) {
                 /* Is our newly found script deeper than the last one we found? */
-                JSScript *incumbent = p->value;
+                JSScript *incumbent = p->value();
                 if (script->staticLevel > incumbent->staticLevel)
-                    p->value = script;
+                    p->value() = script;
             } else {
                 /*
                  * This is the first matching script we've encountered for this
@@ -2818,8 +2818,8 @@ Debugger::wrapScript(JSContext *cx, HandleScript script)
         }
     }
 
-    JS_ASSERT(GetScriptReferent(p->value) == script);
-    return p->value;
+    JS_ASSERT(GetScriptReferent(p->value()) == script);
+    return p->value();
 }
 
 static JSObject *
@@ -3711,8 +3711,8 @@ Debugger::wrapSource(JSContext *cx, HandleScriptSource source)
         }
     }
 
-    JS_ASSERT(GetSourceReferent(p->value) == source);
-    return p->value;
+    JS_ASSERT(GetSourceReferent(p->value()) == source);
+    return p->value();
 }
 
 static bool
diff --git a/js/src/vm/Debugger.h b/js/src/vm/Debugger.h
index 323998805b2..b10df4e42de 100644
--- a/js/src/vm/Debugger.h
+++ b/js/src/vm/Debugger.h
@@ -107,9 +107,9 @@ class DebuggerWeakMap : private WeakMap<Key, Value, DefaultHasher<Key> >
   public:
     void markKeys(JSTracer *tracer) {
         for (Enum e(*static_cast<Base *>(this)); !e.empty(); e.popFront()) {
-            Key key = e.front().key;
+            Key key = e.front().key();
             gc::Mark(tracer, &key, "Debugger WeakMap key");
-            if (key != e.front().key)
+            if (key != e.front().key())
                 e.rekeyFront(key);
             key.unsafeSet(nullptr);
         }
@@ -117,7 +117,7 @@ class DebuggerWeakMap : private WeakMap<Key, Value, DefaultHasher<Key> >
 
     bool hasKeyInZone(JS::Zone *zone) {
         CountMap::Ptr p = zoneCounts.lookup(zone);
-        JS_ASSERT_IF(p, p->value > 0);
+        JS_ASSERT_IF(p, p->value() > 0);
         return p;
     }
 
@@ -125,7 +125,7 @@ class DebuggerWeakMap : private WeakMap<Key, Value, DefaultHasher<Key> >
     /* Override sweep method to also update our edge cache. */
     void sweep() {
         for (Enum e(*static_cast<Base *>(this)); !e.empty(); e.popFront()) {
-            Key k(e.front().key);
+            Key k(e.front().key());
             if (gc::IsAboutToBeFinalized(&k)) {
                 e.removeFront();
                 decZoneCount(k->zone());
@@ -138,16 +138,16 @@ class DebuggerWeakMap : private WeakMap<Key, Value, DefaultHasher<Key> >
         CountMap::Ptr p = zoneCounts.lookupWithDefault(zone, 0);
         if (!p)
             return false;
-        ++p->value;
+        ++p->value();
         return true;
     }
 
     void decZoneCount(JS::Zone *zone) {
         CountMap::Ptr p = zoneCounts.lookup(zone);
         JS_ASSERT(p);
-        JS_ASSERT(p->value > 0);
-        --p->value;
-        if (p->value == 0)
+        JS_ASSERT(p->value() > 0);
+        --p->value();
+        if (p->value() == 0)
             zoneCounts.remove(zone);
     }
 };
diff --git a/js/src/vm/MemoryMetrics.cpp b/js/src/vm/MemoryMetrics.cpp
index 3175beeb994..ef93142822e 100644
--- a/js/src/vm/MemoryMetrics.cpp
+++ b/js/src/vm/MemoryMetrics.cpp
@@ -289,7 +289,7 @@ StatsCellCallback(JSRuntime *rt, void *data, void *thing, JSGCTraceKind traceKin
                                     normalStringThingSize, strCharsSize);
                 zStats->strings.add(p, str, info);
             } else {
-                p->value.add(shortStringThingSize, normalStringThingSize, strCharsSize);
+                p->value().add(shortStringThingSize, normalStringThingSize, strCharsSize);
             }
         }
 
@@ -393,8 +393,8 @@ FindNotableStrings(ZoneStats &zStats)
 
     for (ZoneStats::StringsHashMap::Range r = zStats.strings.all(); !r.empty(); r.popFront()) {
 
-        JSString *str = r.front().key;
-        StringInfo &info = r.front().value;
+        JSString *str = r.front().key();
+        StringInfo &info = r.front().value();
 
         // If this string is too small, or if we can't grow the notableStrings
         // vector, skip this string.
diff --git a/js/src/vm/RegExpObject.cpp b/js/src/vm/RegExpObject.cpp
index 1152ba3552f..5c42bc2b0ce 100644
--- a/js/src/vm/RegExpObject.cpp
+++ b/js/src/vm/RegExpObject.cpp
@@ -669,7 +669,7 @@ RegExpCompartment::sweep(JSRuntime *rt)
 {
 #ifdef DEBUG
     for (Map::Range r = map_.all(); !r.empty(); r.popFront())
-        JS_ASSERT(inUse_.has(r.front().value));
+        JS_ASSERT(inUse_.has(r.front().value()));
 #endif
 
     map_.clear();
@@ -696,7 +696,7 @@ RegExpCompartment::get(ExclusiveContext *cx, JSAtom *source, RegExpFlag flags, R
     Key key(source, flags);
     Map::AddPtr p = map_.lookupForAdd(key);
     if (p) {
-        g->init(*p->value);
+        g->init(*p->value());
         return true;
     }
 
diff --git a/js/src/vm/SPSProfiler.cpp b/js/src/vm/SPSProfiler.cpp
index e3d19ea1160..a968778a00d 100644
--- a/js/src/vm/SPSProfiler.cpp
+++ b/js/src/vm/SPSProfiler.cpp
@@ -33,7 +33,7 @@ SPSProfiler::~SPSProfiler()
 {
     if (strings.initialized()) {
         for (ProfileStringMap::Enum e(strings); !e.empty(); e.popFront())
-            js_free(const_cast<char *>(e.front().value));
+            js_free(const_cast<char *>(e.front().value()));
     }
 }
 
@@ -80,7 +80,7 @@ SPSProfiler::profileString(JSContext *cx, JSScript *script, JSFunction *maybeFun
     JS_ASSERT(strings.initialized());
     ProfileStringMap::AddPtr s = strings.lookupForAdd(script);
     if (s)
-        return s->value;
+        return s->value();
     const char *str = allocProfileString(cx, script, maybeFun);
     if (str == nullptr)
         return nullptr;
@@ -104,7 +104,7 @@ SPSProfiler::onScriptFinalized(JSScript *script)
     if (!strings.initialized())
         return;
     if (ProfileStringMap::Ptr entry = strings.lookup(script)) {
-        const char *tofree = entry->value;
+        const char *tofree = entry->value();
         strings.remove(entry);
         js_free(const_cast<char *>(tofree));
     }
diff --git a/js/src/vm/ScopeObject.cpp b/js/src/vm/ScopeObject.cpp
index 740df8ff9ec..8e0aa3365a2 100644
--- a/js/src/vm/ScopeObject.cpp
+++ b/js/src/vm/ScopeObject.cpp
@@ -94,7 +94,7 @@ js::ScopeCoordinateName(ScopeCoordinateNameCache &cache, JSScript *script, jsbyt
     ScopeCoordinate sc(pc);
     if (shape == cache.shape) {
         ScopeCoordinateNameCache::Map::Ptr p = cache.map.lookup(sc.slot);
-        id = p->value;
+        id = p->value();
     } else {
         Shape::Range<NoGC> r(shape);
         while (r.front().slot() != sc.slot)
@@ -1592,13 +1592,13 @@ DebugScopes::sweep(JSRuntime *rt)
      * creating an uncollectable cycle with suspended generator frames.
      */
     for (MissingScopeMap::Enum e(missingScopes); !e.empty(); e.popFront()) {
-        if (IsObjectAboutToBeFinalized(e.front().value.unsafeGet()))
+        if (IsObjectAboutToBeFinalized(e.front().value().unsafeGet()))
             e.removeFront();
     }
 
     for (LiveScopeMap::Enum e(liveScopes); !e.empty(); e.popFront()) {
-        ScopeObject *scope = e.front().key;
-        AbstractFramePtr frame = e.front().value;
+        ScopeObject *scope = e.front().key();
+        AbstractFramePtr frame = e.front().value();
 
         /*
          * Scopes can be finalized when a debugger-synthesized ScopeObject is
@@ -1661,7 +1661,7 @@ DebugScopes::hasDebugScope(JSContext *cx, ScopeObject &scope)
 
     if (ObjectWeakMap::Ptr p = scopes->proxiedScopes.lookup(&scope)) {
         JS_ASSERT(CanUseDebugScopeMaps(cx));
-        return &p->value->as<DebugScopeObject>();
+        return &p->value()->as<DebugScopeObject>();
     }
 
     return nullptr;
@@ -1701,7 +1701,7 @@ DebugScopes::hasDebugScope(JSContext *cx, const ScopeIter &si)
 
     if (MissingScopeMap::Ptr p = scopes->missingScopes.lookup(si)) {
         JS_ASSERT(CanUseDebugScopeMaps(cx));
-        return p->value;
+        return p->value();
     }
     return nullptr;
 }
@@ -1758,11 +1758,11 @@ DebugScopes::onPopCall(AbstractFramePtr frame, JSContext *cx)
         CallObject &callobj = frame.scopeChain()->as<CallObject>();
         scopes->liveScopes.remove(&callobj);
         if (ObjectWeakMap::Ptr p = scopes->proxiedScopes.lookup(&callobj))
-            debugScope = &p->value->as<DebugScopeObject>();
+            debugScope = &p->value()->as<DebugScopeObject>();
     } else {
         ScopeIter si(frame, cx);
         if (MissingScopeMap::Ptr p = scopes->missingScopes.lookup(si)) {
-            debugScope = p->value;
+            debugScope = p->value();
             scopes->liveScopes.remove(&debugScope->scope().as<CallObject>());
             scopes->missingScopes.remove(p);
         }
@@ -1831,7 +1831,7 @@ DebugScopes::onPopBlock(JSContext *cx, AbstractFramePtr frame)
     } else {
         ScopeIter si(frame, cx);
         if (MissingScopeMap::Ptr p = scopes->missingScopes.lookup(si)) {
-            ClonedBlockObject &clone = p->value->scope().as<ClonedBlockObject>();
+            ClonedBlockObject &clone = p->value()->scope().as<ClonedBlockObject>();
             clone.copyUnaliasedValues(frame);
             scopes->liveScopes.remove(&clone);
             scopes->missingScopes.remove(p);
@@ -1881,7 +1881,7 @@ DebugScopes::onGeneratorFrameChange(AbstractFramePtr from, AbstractFramePtr to,
             JS_ASSERT(toIter.scope().compartment() == cx->compartment());
             LiveScopeMap::AddPtr livePtr = scopes->liveScopes.lookupForAdd(&toIter.scope());
             if (livePtr) {
-                livePtr->value = to;
+                livePtr->value() = to;
             } else {
                 scopes->liveScopes.add(livePtr, &toIter.scope(), to);  // OOM here?
                 liveScopesPostWriteBarrier(cx->runtime(), &scopes->liveScopes, &toIter.scope());
@@ -1890,8 +1890,8 @@ DebugScopes::onGeneratorFrameChange(AbstractFramePtr from, AbstractFramePtr to,
             ScopeIter si(toIter, from, cx);
             JS_ASSERT(si.frame().scopeChain()->compartment() == cx->compartment());
             if (MissingScopeMap::Ptr p = scopes->missingScopes.lookup(si)) {
-                DebugScopeObject &debugScope = *p->value;
-                scopes->liveScopes.lookup(&debugScope.scope())->value = to;
+                DebugScopeObject &debugScope = *p->value();
+                scopes->liveScopes.lookup(&debugScope.scope())->value() = to;
                 scopes->missingScopes.remove(p);
                 scopes->missingScopes.put(toIter, &debugScope);  // OOM here?
             }
@@ -1967,7 +1967,7 @@ DebugScopes::hasLiveFrame(ScopeObject &scope)
         return NullFramePtr();
 
     if (LiveScopeMap::Ptr p = scopes->liveScopes.lookup(&scope)) {
-        AbstractFramePtr frame = p->value;
+        AbstractFramePtr frame = p->value();
 
         /*
          * Since liveScopes is effectively a weak pointer, we need a read
diff --git a/js/src/vm/SelfHosting.cpp b/js/src/vm/SelfHosting.cpp
index 82e43976456..e518e00f759 100644
--- a/js/src/vm/SelfHosting.cpp
+++ b/js/src/vm/SelfHosting.cpp
@@ -891,7 +891,7 @@ CloneObject(JSContext *cx, HandleObject srcObj, CloneMemory &clonedObjects)
 {
     DependentAddPtr<CloneMemory> p(cx, clonedObjects, srcObj.get());
     if (p)
-        return p->value;
+        return p->value();
     RootedObject clone(cx);
     if (srcObj->is<JSFunction>()) {
         if (srcObj->as<JSFunction>().isWrappable()) {
diff --git a/js/src/vm/StructuredClone.cpp b/js/src/vm/StructuredClone.cpp
index c174955e410..171cf9238b1 100644
--- a/js/src/vm/StructuredClone.cpp
+++ b/js/src/vm/StructuredClone.cpp
@@ -829,7 +829,7 @@ JSStructuredCloneWriter::startObject(HandleObject obj, bool *backref)
     /* Handle cycles in the object graph. */
     CloneMemory::AddPtr p = memory.lookupForAdd(obj);
     if ((*backref = p))
-        return out.writePair(SCTAG_BACK_REFERENCE_OBJECT, p->value);
+        return out.writePair(SCTAG_BACK_REFERENCE_OBJECT, p->value());
     if (!memory.add(p, obj, memory.count()))
         return false;
 
diff --git a/js/xpconnect/src/XPCMaps.cpp b/js/xpconnect/src/XPCMaps.cpp
index 152d0041b73..ebde7ef0152 100644
--- a/js/xpconnect/src/XPCMaps.cpp
+++ b/js/xpconnect/src/XPCMaps.cpp
@@ -85,7 +85,7 @@ void
 JSObject2WrappedJSMap::FindDyingJSObjects(nsTArray<nsXPCWrappedJS*>* dying)
 {
     for (Map::Range r = mTable.all(); !r.empty(); r.popFront()) {
-        nsXPCWrappedJS* wrapper = r.front().value;
+        nsXPCWrappedJS* wrapper = r.front().value();
         MOZ_ASSERT(wrapper, "found a null JS wrapper!");
 
         // walk the wrapper chain and find any whose JSObject is to be finalized
@@ -101,7 +101,7 @@ void
 JSObject2WrappedJSMap::ShutdownMarker()
 {
     for (Map::Range r = mTable.all(); !r.empty(); r.popFront()) {
-        nsXPCWrappedJS* wrapper = r.front().value;
+        nsXPCWrappedJS* wrapper = r.front().value();
         MOZ_ASSERT(wrapper, "found a null JS wrapper!");
         MOZ_ASSERT(wrapper->IsValid(), "found an invalid JS wrapper!");
         wrapper->SystemIsBeingShutDown();
diff --git a/js/xpconnect/src/XPCMaps.h b/js/xpconnect/src/XPCMaps.h
index 0cc7c358eae..0c44bcd3f00 100644
--- a/js/xpconnect/src/XPCMaps.h
+++ b/js/xpconnect/src/XPCMaps.h
@@ -41,7 +41,7 @@ public:
     inline nsXPCWrappedJS* Find(JSObject* Obj) {
         NS_PRECONDITION(Obj,"bad param");
         Map::Ptr p = mTable.lookup(Obj);
-        return p ? p->value : nullptr;
+        return p ? p->value() : nullptr;
     }
 
     inline nsXPCWrappedJS* Add(JSContext* cx, nsXPCWrappedJS* wrapper) {
@@ -49,7 +49,7 @@ public:
         JSObject* obj = wrapper->GetJSObjectPreserveColor();
         Map::AddPtr p = mTable.lookupForAdd(obj);
         if (p)
-            return p->value;
+            return p->value();
         if (!mTable.add(p, obj, wrapper))
             return nullptr;
         JS_StoreObjectPostBarrierCallback(cx, KeyMarkCallback, obj, this);
@@ -65,7 +65,7 @@ public:
 
     inline void Dump(int16_t depth) {
         for (Map::Range r = mTable.all(); !r.empty(); r.popFront())
-            r.front().value->DebugDump(depth);
+            r.front().value()->DebugDump(depth);
     }
 
     void FindDyingJSObjects(nsTArray<nsXPCWrappedJS*>* dying);
@@ -634,7 +634,7 @@ public:
     inline JSObject* Find(JSObject* key) {
         NS_PRECONDITION(key, "bad param");
         if (Map::Ptr p = mTable.lookup(key))
-            return p->value;
+            return p->value();
         return nullptr;
     }
 
@@ -643,7 +643,7 @@ public:
         NS_PRECONDITION(key,"bad param");
         Map::AddPtr p = mTable.lookupForAdd(key);
         if (p)
-            return p->value;
+            return p->value();
         if (!mTable.add(p, key, value))
             return nullptr;
         MOZ_ASSERT(xpc::GetCompartmentPrivate(key)->scope->mWaiverWrapperMap == this);
@@ -660,10 +660,10 @@ public:
 
     void Sweep() {
         for (Map::Enum e(mTable); !e.empty(); e.popFront()) {
-            JSObject *updated = e.front().key;
-            if (JS_IsAboutToBeFinalizedUnbarriered(&updated) || JS_IsAboutToBeFinalized(&e.front().value))
+            JSObject *updated = e.front().key();
+            if (JS_IsAboutToBeFinalizedUnbarriered(&updated) || JS_IsAboutToBeFinalized(&e.front().value()))
                 e.removeFront();
-            else if (updated != e.front().key)
+            else if (updated != e.front().key())
                 e.rekeyFront(updated);
         }
     }
@@ -675,12 +675,12 @@ public:
              * We reparent wrappers that have as their parent an inner window
              * whose outer has the new inner window as its current inner.
              */
-            JS::RootedObject parent(aCx, JS_GetParent(e.front().value));
+            JS::RootedObject parent(aCx, JS_GetParent(e.front().value()));
             JS::RootedObject outer(aCx, JS_ObjectToOuterObject(aCx, parent));
             if (outer) {
                 JSObject *inner = JS_ObjectToInnerObject(aCx, outer);
                 if (inner == aNewInner && inner != parent)
-                    JS_SetParent(aCx, e.front().value, aNewInner);
+                    JS_SetParent(aCx, e.front().value(), aNewInner);
             } else {
                 JS_ClearPendingException(aCx);
             }
diff --git a/layout/style/nsNthIndexCache.cpp b/layout/style/nsNthIndexCache.cpp
index 63e2c8d9985..07ac7c1d2f1 100644
--- a/layout/style/nsNthIndexCache.cpp
+++ b/layout/style/nsNthIndexCache.cpp
@@ -48,7 +48,7 @@ nsNthIndexCache::IndexDeterminedFromPreviousSibling(nsIContent* aSibling,
   if (SiblingMatchesElement(aSibling, aChild, aIsOfType)) {
     Cache::Ptr siblingEntry = aCache.lookup(aSibling);
     if (siblingEntry) {
-      int32_t siblingIndex = siblingEntry->value;
+      int32_t siblingIndex = siblingEntry->value();
       NS_ASSERTION(siblingIndex != 0,
                    "How can a non-anonymous node have an anonymous sibling?");
       if (siblingIndex > 0) {
@@ -93,7 +93,7 @@ nsNthIndexCache::GetNthIndex(Element* aChild, bool aIsOfType,
     return 0;
   }
 
-  int32_t &slot = entry->value;
+  int32_t &slot = entry->value();
   if (slot != -2 && (slot != -1 || aCheckEdgeOnly)) {
     return slot;
   }