diff --git a/pui/container.h b/pui/container.h
index 6d58078..a9cf365 100644
--- a/pui/container.h
+++ b/pui/container.h
@@ -28,6 +28,8 @@ public:
 	int back;
 	int padding;
 
+	Container() : back(0), padding(0) {}
+
 	~Container();
 
 	/* virtual */ Widget *GetWidget(int x, int y);
diff --git a/pui/pui.h b/pui/pui.h
index 9be2948..676fb55 100644
--- a/pui/pui.h
+++ b/pui/pui.h
@@ -35,6 +35,8 @@ struct PUi : PTextures {
 	int mx, my, mb, mm;
 	float scale;
 
+	PUi() : view(NULL), widget(NULL), tooltip(NULL), active(NULL), mx(0), my(0), mb(0), mm(0), scale(1.f) {}
+
 	virtual ~PUi();
 
 	inline void Repaint() { puglPostRedisplay(this->view); }
diff --git a/pui/textures.h b/pui/textures.h
index 50ed873..20c8a60 100644
--- a/pui/textures.h
+++ b/pui/textures.h
@@ -40,6 +40,8 @@ struct PTextures {
 
 	FTFont *font;
 
+	PTextures() : initialised(false) {}
+
 	void InitTextures();
 	void BindTexture(int texture, int width, int height, const unsigned char *data, int format = GL_RGBA);
 };
diff --git a/pui/widget.h b/pui/widget.h
index d03a460..170b3a2 100644
--- a/pui/widget.h
+++ b/pui/widget.h
@@ -25,6 +25,8 @@ struct Rect {
 	int w;
 	int h;
 
+	Rect() : x(0), y(0), w(0), h(0) {}
+
 	inline bool Hit(int hitx, int hity)
 	{
 		return hitx >= x && hitx < x + w && hity >= y && hity < y + h;
@@ -34,7 +36,7 @@ struct Rect {
 struct Colour {
 	float r, g, b, a;
 
-	Colour() {}
+	Colour() : r(0), g(0), b(0), a(0) {}
 	Colour(float r, float g, float b) : r(r), g(g), b(b), a(1.f) {}
 	Colour(float r, float g, float b, float a) : r(r), g(g), b(b), a(a) {}
 };
@@ -53,7 +55,7 @@ struct Widget : Rect {
 
 	bool active;
 
-	Widget() : port(UINT_MAX) {}
+	Widget() : port(UINT_MAX), min(0.f), max(1.f), value(0.f), active(false) {}
 
 	virtual ~Widget() {}