Fix a few minor compiler warnings

src/modules/audio/openal/Pool.cpp

@@ -34,7 +34,7 @@ static Variant::SharedTable *putSourcesAsSharedTable(std::vector<audio::Source *
 {
 	Variant::SharedTable *table = new Variant::SharedTable();
 
-	for (int i = 0; i < sources.size(); i++)
+	for (int i = 0; i < (int) sources.size(); i++)
 		table->pairs.emplace_back((double) (i + 1), Variant(&Source::type, sources[i]));
 
 	return table;

src/modules/data/DataStream.cpp

@@ -34,19 +34,19 @@ love::Type DataStream::type("DataStream", &Stream::type);
 
 DataStream::DataStream(Data *data)
 	: data(data)
-	, offset(0)
-	, size(data->getSize())
 	, memory((const uint8 *) data->getData())
 	, writableMemory((uint8 *) data->getData()) // TODO: disallow writing sometimes?
+	, offset(0)
+	, size(data->getSize())
 {
 }
 
 DataStream::DataStream(const DataStream &other)
 	: data(other.data)
-	, offset(0)
-	, size(other.size)
 	, memory(other.memory)
 	, writableMemory(other.writableMemory)
+	, offset(0)
+	, size(other.size)
 {
 }
 
@@ -79,7 +79,7 @@ int64 DataStream::read(void* data, int64 size)
 	if (size <= 0)
 		return 0;
 
-	if (offset >= getSize())
+	if ((int64) offset >= getSize())
 		return 0;
 
 	int64 readsize = std::min<int64>(size, getSize() - offset);
@@ -95,7 +95,7 @@ bool DataStream::write(const void* data, int64 size)
 	if (size <= 0 || writableMemory == nullptr)
 		return false;
 
-	if (offset >= getSize())
+	if ((int64) offset >= getSize())
 		return false;
 
 	int64 writesize = std::min<int64>(size, getSize() - offset);
@@ -123,7 +123,7 @@ bool DataStream::seek(int64 pos, SeekOrigin origin)
 	else if (origin == SEEKORIGIN_END)
 		pos += size;
 
-	if (pos < 0 || pos > size)
+	if (pos < 0 || pos > (int64) size)
 		return false;
 
 	offset = pos;

src/modules/system/sdl/System.h

@@ -43,14 +43,14 @@ public:
 	virtual ~System() {}
 
 	// Implements Module.
-	const char *getName() const;
+	const char *getName() const override;
 
-	int getProcessorCount() const;
+	int getProcessorCount() const override;
 
-	void setClipboardText(const std::string &text) const;
-	std::string getClipboardText() const;
+	void setClipboardText(const std::string &text) const override;
+	std::string getClipboardText() const override;
 
-	PowerState getPowerInfo(int &seconds, int &percent) const;
+	PowerState getPowerInfo(int &seconds, int &percent) const override;
 	std::vector<std::string> getPreferredLocales() const override;
 
 private: