Some fixes detected by xcode analyze

cocos/2d/CCFontAtlas.cpp

@@ -237,7 +237,7 @@ bool FontAtlas::prepareLetterDefinitions(unsigned short *utf16String)
 
     bool existNewLetter = false;
     int bottomHeight = _commonLineHeight - _fontAscender;
-    float startX = _currentPageOrigX;
+
     float startY = _currentPageOrigY;
 
     for (int i = 0; i < length; ++i)
@@ -268,7 +268,7 @@ bool FontAtlas::prepareLetterDefinitions(unsigned short *utf16String)
                         auto data = _currentPageData + CacheTextureWidth * (int)startY;
                         _atlasTextures[_currentPage]->updateWithData(data, 0, startY, 
                             CacheTextureWidth, CacheTextureHeight - startY);
-                        startX = 0.0f;
+
                         startY = 0.0f;
 
                         _currentPageOrigY = 0;

cocos/2d/CCFontFreeType.cpp

@@ -497,7 +497,7 @@ void FontFreeType::renderCharAt(unsigned char *dest,int posX, int posY, unsigned
         {
             long bitmap_y = y * bitmapWidth;
 
-            for (int x = 0; x < bitmapWidth; ++x)
+            for (long x = 0; x < bitmapWidth; ++x)
             {    
                 /* Dual channel 16-bit output (more complicated, but good precision and range) */
                 /*int index = (iX + ( iY * destSize )) * 3;                

cocos/2d/CCLabel.cpp

@@ -1081,16 +1081,18 @@ void Label::drawTextSprite(Renderer *renderer, bool parentTransformUpdated)
     if (_shadowEnabled && _shadowNode == nullptr)
     {
         _shadowNode = Sprite::createWithTexture(_textSprite->getTexture());
-        if (_shadowNode && _blendFuncDirty)
+        if (_shadowNode)
         {
+            if (_blendFuncDirty)
                 _shadowNode->setBlendFunc(_blendFunc);
-        }
+            
             _shadowNode->setAnchorPoint(Point::ANCHOR_BOTTOM_LEFT);
             _shadowNode->setColor(_shadowColor);
             _shadowNode->setOpacity(_shadowOpacity * _displayedOpacity);
             _shadowNode->setPosition(_shadowOffset.width, _shadowOffset.height);
             Node::addChild(_shadowNode,0,Node::INVALID_TAG);
         }
+    }
     if (_shadowNode)
     {
         _shadowNode->visit(renderer, _modelViewTransform, parentTransformUpdated);
@@ -1236,7 +1238,7 @@ void Label::computeStringNumLines()
 {
     int quantityOfLines = 1;
 
-    unsigned int stringLen = _currentUTF16String ? cc_wcslen(_currentUTF16String) : -1;
+    int stringLen = _currentUTF16String ? cc_wcslen(_currentUTF16String) : -1;
     if (stringLen < 1)
     {
         _currNumLines = stringLen;
@@ -1244,7 +1246,7 @@ void Label::computeStringNumLines()
     }
 
     // count number of lines
-    for (unsigned int i = 0; i < stringLen - 1; ++i)
+    for (int i = 0; i < stringLen - 1; ++i)
     {
         if (_currentUTF16String[i] == '\n')
         {

cocos/2d/CCNodeGrid.cpp

@@ -105,7 +105,7 @@ void NodeGrid::visit(Renderer *renderer, const kmMat4 &parentTransform, bool par
     kmGLPushMatrix();
     kmGLLoadMatrix(&_modelViewTransform);
 
-    Director::Projection beforeProjectionType;
+    Director::Projection beforeProjectionType = Director::Projection::DEFAULT;
     if(_nodeGrid && _nodeGrid->isActive())
     {
         beforeProjectionType = Director::getInstance()->getProjection();

cocos/2d/CCTextureAtlas.cpp

@@ -483,6 +483,7 @@ bool TextureAtlas::resizeCapacity(ssize_t newCapacity)
         {
             memset(tmpQuads+oldCapactiy, 0, (_capacity - oldCapactiy)*sizeof(_quads[0]) );
         }
+        _quads = nullptr;
     }
 
     if (_indices == nullptr)
@@ -492,7 +493,6 @@ bool TextureAtlas::resizeCapacity(ssize_t newCapacity)
         {
             memset( tmpIndices, 0, _capacity * 6 * sizeof(_indices[0]) );
         }
-        
     }
     else
     {
@@ -501,6 +501,7 @@ bool TextureAtlas::resizeCapacity(ssize_t newCapacity)
         {
             memset( tmpIndices+oldCapactiy, 0, (_capacity-oldCapactiy) * 6 * sizeof(_indices[0]) );
         }
+        _indices = nullptr;
     }
 
     if( ! ( tmpQuads && tmpIndices) ) {

cocos/2d/platform/CCGLViewProtocol.cpp

@@ -250,7 +250,6 @@ void GLViewProtocol::handleTouchesBegin(int num, intptr_t ids[], float xs[], flo
         y = ys[i];
 
         auto iter = g_touchIdReorderMap.find(id);
-        unusedIndex = 0;
 
         // it is a new touch
         if (iter == g_touchIdReorderMap.end())

cocos/2d/platform/CCImage.cpp

@@ -1552,7 +1552,7 @@ bool Image::initWithTGAData(tImageTGA* tgaData)
     }
     else
     {
-        if (tgaData->imageData != nullptr)
+        if (tgaData && tgaData->imageData != nullptr)
         {
             free(tgaData->imageData);
             _data = nullptr;

cocos/ui/UILayout.cpp

@@ -1003,23 +1003,19 @@ const Rect& Layout::getClippingRect()
         float scissorHeight = _size.height*t.d;
         Rect parentClippingRect;
         Layout* parent = this;
-        bool firstClippingParentFounded = false;
+
         while (parent)
         {
             parent = dynamic_cast<Layout*>(parent->getParent());
             if(parent)
             {
                 if (parent->isClippingEnabled())
-                {
-                    if (!firstClippingParentFounded)
                 {
                     _clippingParent = parent;
-                        firstClippingParentFounded = true;
                     break;
                 }
             }
         }
-        }
         
         if (_clippingParent)
         {