Initialization of block pointer variable with incompatible block using wrong syntax passes without error or warning

nowarninghere.m

#import <Foundation/Foundation.h>

int main(int argc, char *argv[]) {
	@autoreleasepool {
		/*Note the use of Objective-C method-style return type syntax.
		 *That's not actually the correct syntax, but the incorrect syntax passes compilation
		 *without a warning even though these blocks have different and incompatible signatures!
		 */
		id (^wat)(int x, int y) = (id)^(CGFloat x, CGFloat y) {
			return @(hypot(x, y));
		};

		NSLog(@"Expected result: %f", hypot(640, 480));
		NSLog(@"Actual result: %@", wat(640, 480));
	}
}