Fix uninitialized variable compiler errors [GCC 4.8.4]

R=svenpanne@chromium.org, michael_dawson@ca.ibm.com
BUG=

Review URL: https://codereview.chromium.org/1163143005

Cr-Commit-Position: refs/heads/master@{#28835}

src/api.cc

@@ -3665,7 +3665,7 @@ i::MaybeHandle<i::Object> DeleteObjectProperty(
     i::Isolate* isolate, i::Handle<i::JSReceiver> receiver,
     i::Handle<i::Object> key, i::LanguageMode language_mode) {
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     // In Firefox/SpiderMonkey, Safari and Opera you can access the
     // characters of a string using [] notation.  In the case of a
@@ -3976,7 +3976,7 @@ Maybe<bool> v8::Object::Has(Local<Context> context, Local<Value> key) {
   auto key_obj = Utils::OpenHandle(*key);
   Maybe<bool> maybe = Nothing<bool>();
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key_obj->ToArrayIndex(&index)) {
     maybe = i::JSReceiver::HasElement(self, index);
   } else {

src/objects-inl.h

@@ -1887,7 +1887,7 @@ void JSObject::EnsureCanContainElements(Handle<JSObject> object,
 
 
 bool JSObject::WouldConvertToSlowElements(Handle<Object> key) {
-  uint32_t index;
+  uint32_t index = 0;
   return key->ToArrayIndex(&index) && WouldConvertToSlowElements(index);
 }
 

src/runtime/runtime-classes.cc

@@ -306,7 +306,7 @@ RUNTIME_FUNCTION(Runtime_LoadKeyedFromSuper) {
   CONVERT_ARG_HANDLE_CHECKED(JSObject, home_object, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, key, 2);
 
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     return LoadElementFromSuper(isolate, receiver, home_object, index);
   }
@@ -394,7 +394,7 @@ static Object* StoreKeyedToSuper(Isolate* isolate, Handle<JSObject> home_object,
                                  Handle<Object> receiver, Handle<Object> key,
                                  Handle<Object> value,
                                  LanguageMode language_mode) {
-  uint32_t index;
+  uint32_t index = 0;
 
   if (key->ToArrayIndex(&index)) {
     return StoreElementToSuper(isolate, home_object, receiver, index, value,

src/runtime/runtime-object.cc

@@ -61,7 +61,7 @@ MaybeHandle<Object> Runtime::GetObjectProperty(Isolate* isolate,
   }
 
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     return GetElementOrCharAt(isolate, object, index);
   }
@@ -106,7 +106,7 @@ MaybeHandle<Object> Runtime::SetObjectProperty(Isolate* isolate,
   }
 
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     // TODO(verwaest): Support non-JSObject receivers.
     if (!object->IsJSObject()) return value;
@@ -182,7 +182,7 @@ MaybeHandle<Object> Runtime::DefineObjectProperty(Handle<JSObject> js_object,
                                                   PropertyAttributes attrs) {
   Isolate* isolate = js_object->GetIsolate();
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     // In Firefox/SpiderMonkey, Safari and Opera you can access the characters
     // of a string using [] notation.  We need to support this too in

src/runtime/runtime-scopes.cc

@@ -1063,7 +1063,7 @@ RUNTIME_FUNCTION(Runtime_GetArgumentsProperty) {
 
   // Try to convert the key to an index. If successful and within
   // index return the the argument from the frame.
-  uint32_t index;
+  uint32_t index = 0;
   if (raw_key->ToArrayIndex(&index) && index < n) {
     return frame->GetParameter(index);
   }

src/runtime/runtime-strings.cc

@@ -139,7 +139,7 @@ RUNTIME_FUNCTION(Runtime_StringIndexOf) {
   CONVERT_ARG_HANDLE_CHECKED(String, pat, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, index, 2);
 
-  uint32_t start_index;
+  uint32_t start_index = 0;
   if (!index->ToArrayIndex(&start_index)) return Smi::FromInt(-1);
 
   RUNTIME_ASSERT(start_index <= static_cast<uint32_t>(sub->length()));
@@ -190,7 +190,7 @@ RUNTIME_FUNCTION(Runtime_StringLastIndexOf) {
   CONVERT_ARG_HANDLE_CHECKED(String, pat, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, index, 2);
 
-  uint32_t start_index;
+  uint32_t start_index = 0;
   if (!index->ToArrayIndex(&start_index)) return Smi::FromInt(-1);
 
   uint32_t pat_length = pat->length();