Fixed build warnings

GCDWebServer/Core/GCDWebServerPrivate.h

@@ -188,7 +188,7 @@ static inline BOOL GCDWebServerIsValidByteRange(NSRange range) {
 }
 
 static inline NSError* GCDWebServerMakePosixError(int code) {
-  return [NSError errorWithDomain:NSPOSIXErrorDomain code:code userInfo:@{NSLocalizedDescriptionKey : [NSString stringWithUTF8String:strerror(code)]}];
+  return [NSError errorWithDomain:NSPOSIXErrorDomain code:code userInfo:@{NSLocalizedDescriptionKey : (NSString*)[NSString stringWithUTF8String:strerror(code)]}];
 }
 
 extern void GCDWebServerInitializeFunctions();

GCDWebUploader/GCDWebUploader.m

@@ -254,7 +254,7 @@ NS_ASSUME_NONNULL_END
         [array addObject:@{
           @"path" : [relativePath stringByAppendingPathComponent:item],
           @"name" : item,
-          @"size" : [attributes objectForKey:NSFileSize]
+          @"size" : (NSNumber*)[attributes objectForKey:NSFileSize]
         }];
       } else if ([type isEqualToString:NSFileTypeDirectory]) {
         [array addObject:@{