Question

Can I use this string in release code?

NSAssert([entity buildEntity], @"Building failed at entity with id: %d", entity.entityId);

[entity buildEntity] returns BOOL and must be called.

So the question is: if I turn off assertion in release(default behavior of Xcode 4) then will blocks of code inside assertion be executed or not?

Answer 1

NO, buildEntity will not execute in release mode.
Use below code, this will behave same in debug and release mode.

id lValue = [entity buildEntity];
NSAssert(lValue, @"Building failed at entity with id: %d", entity.entityId);