Fixed new clang errors in Xcode 6.3b2

platform/ios/MGLMapView.mm

@@ -646,7 +646,7 @@ mbgl::DefaultFileSource *mbglFileSource = nullptr;
 
         // constrain to +/-30 degrees when merely rotating like Apple does
         //
-        if ( ! self.isRotationAllowed && fabsf(self.pinch.scale) < 10)
+        if ( ! self.isRotationAllowed && std::abs(self.pinch.scale) < 10)
         {
             newDegrees = fminf(newDegrees,  30);
             newDegrees = fmaxf(newDegrees, -30);

src/mbgl/map/tile_parser.cpp

@@ -43,7 +43,6 @@ TileParser::TileParser(const std::string &data, VectorTileData &tile_,
       spriteAtlas(spriteAtlas_),
       sprite(sprite_),
       collision(util::make_unique<Collision>(tile.id.z, 4096, tile.source.tile_size, tile.depth)) {
-    assert(&tile != nullptr);
     assert(style);
     assert(sprite);
     assert(collision);