fix some xcode 7.0 warnings

src/video_core/gpu_debugger.h

@@ -45,7 +45,6 @@ public:
 
     private:
         GraphicsDebugger* observed;
-        bool in_destruction;
 
         friend class GraphicsDebugger;
     };

src/video_core/rasterizer.cpp

@@ -967,6 +967,8 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0,
                         UNIMPLEMENTED();
                         break;
                     }
+
+                    return {};
                 };
 
                 auto LookupFactorA = [&](Regs::BlendFactor factor) -> u8 {
@@ -1000,6 +1002,8 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0,
                         UNIMPLEMENTED();
                         break;
                     }
+
+                    return {};
                 };
 
                 static auto EvaluateBlendEquation = [](const Math::Vec4<u8>& src, const Math::Vec4<u8>& srcfactor,

src/video_core/renderer_opengl/renderer_opengl.h

@@ -62,7 +62,6 @@ private:
                                     const TextureInfo& texture);
 
     EmuWindow*  render_window;                    ///< Handle to render window
-    u32         last_mode;                        ///< Last render mode
 
     int resolution_width;                         ///< Current resolution width
     int resolution_height;                        ///< Current resolution height