displaySize = invalid initializer - size

Question

I have a method where I'm taking a screenshot, but there's 2 problems with it. For the 2 lines
CGSize displaySize = [[CCDirector sharedDirector] displaySize];
CGSize winSize = [[CCDirector sharedDirector] winSize];
I get the warning Invalid initializer for displaySize, and also CCDirector may not respond to '-displaySize'
Oh and I'm using cocos2d...
This is the entire method
-(UIImage *)screenshot {
CGSize displaySize = [[CCDirector sharedDirector] displaySize];
CGSize winSize = [[CCDirector sharedDirector] winSize];
GLuint bufferLength = displaySize.width * winSize.height * 4;
GLubyte *buffer = (GLubyte *) malloc (bufferLength);
glReadPixels(0, 0, displaySize.width, displaySize.height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer, bufferLength, NULL);
int bitsPerComponent = 8;
int bitsPerPixel = 32;
int bytesPerRow = 4 * displaySize.width;
CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();
CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;
CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
CGImageRef iref = CGImageCreate (displaySize.width, displaySize.height, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
uint32_t *pixels = (uint32_t *) malloc (bufferLength);
CGContextRef context = CGBitmapContextCreate(pixels, winSize.width, winSize.height, 8, winSize.width * 4, CGImageGetColorSpace(iref), kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGContextTranslateCTM(context, 0, displaySize.height);
CGContextScaleCTM(context, 1.0f, -1.0f);
CGContextDrawImage(context, CGRectMake(0.0f, 0.0f, displaySize.width, displaySize.height), iref);
CGImageRef imageRef = CGBitmapContextCreateImage(context);
image = [[[UIImage alloc] initWithCGImage:imageRef] autorelease];
NSString *file = #"GameOver_Screenshot.png";
NSString *directory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *path = [directory stringByAppendingPathComponent:file];
[UIImagePNGRepresentation(image) writeToFile:path atomically:YES];
return image;
}

Answer 1

Looks like "CCDirecrot.h" is not imported to the source file
EDIT:
What version of cocos are you using?
http://www.cocos2d-iphone.org/api-ref/0.99.5/interface_c_c_director.html
Here is no displaySize method for example
Also try to write this
CCDirector *director = [CCDirector shareDirector];
and check with debugger director is correct.
If director is correct then check with debugger what values are put in winSize and displaySize or when the application is crashing.