Fixing some particularly bad /W4.

src/xenia/vfs/devices/stfs_container_device.cc

@@ -224,7 +224,7 @@ StfsContainerDevice::Error StfsContainerDevice::ReadAllEntries(
 
 size_t StfsContainerDevice::BlockToOffset(uint32_t block) {
   if (block >= 0xFFFFFF) {
-    return -1;
+    return ~0ull;
   } else {
     return ((header_.header_size + 0x0FFF) & 0xF000) + (block << 12);
   }

src/xenia/vfs/entry.cc

@@ -100,7 +100,7 @@ bool Entry::Delete(Entry* entry) {
   if (!DeleteEntryInternal(entry)) {
     return false;
   }
-  for (auto& it = children_.begin(); it != children_.end(); ++it) {
+  for (auto it = children_.begin(); it != children_.end(); ++it) {
     if (it->get() == entry) {
       children_.erase(it);
       break;

src/xenia/vfs/virtual_file_system.cc

@@ -41,7 +41,7 @@ bool VirtualFileSystem::RegisterSymbolicLink(std::string path,
 
 bool VirtualFileSystem::UnregisterSymbolicLink(std::string path) {
   std::lock_guard<xe::mutex> lock(mutex_);
-  auto& it = symlinks_.find(path);
+  auto it = symlinks_.find(path);
   if (it == symlinks_.end()) {
     return false;
   }