OBJ_HELP=1

objc[13184]: OBJC_HELP: describe Objective-C runtime environment variables
objc[13184]: OBJC_PRINT_OPTIONS: list which options are set
objc[13184]: OBJC_PRINT_IMAGES: log image and library names as they are loaded
objc[13184]: OBJC_PRINT_LOAD_METHODS: log calls to class and category +load methods
objc[13184]: OBJC_PRINT_INITIALIZE_METHODS: log calls to class +initialize methods
objc[13184]: OBJC_PRINT_RESOLVED_METHODS: log methods created by +resolveClassMethod: and +resolveInstanceMethod:
objc[13184]: OBJC_PRINT_CLASS_SETUP: log progress of class and category setup
objc[13184]: OBJC_PRINT_PROTOCOL_SETUP: log progresso of protocol setup
objc[13184]: OBJC_PRINT_IVAR_SETUP: log processing of non-fragile ivars
objc[13184]: OBJC_PRINT_FUTURE_CLASSES: log use of future classes for toll-free bridging
objc[13184]: OBJC_PRINT_RTP: log initialization of the Objective-C runtime pages
objc[13184]: OBJC_PRINT_GC: log some GC operations
objc[13184]: OBJC_PRINT_SHARING: log cross-process memory sharing
objc[13184]: OBJC_PRINT_CXX_CTORS: log calls to C++ ctors and dtors for instance variables
objc[13184]: OBJC_PRINT_EXCEPTIONS: log exception handling
objc[13184]: OBJC_PRINT_ALT_HANDLERS: log processing of exception alt handlers
objc[13184]: OBJC_PRINT_REPLACED_METHODS: log methods replaced by category implementations
objc[13184]: OBJC_PRINT_DEPRECATION_WARNINGS: warn about calls to deprecated runtime functions
objc[13184]: OBJC_PRINT_CACHE_COLLECTION: log cleanup of stale method caches
objc[13184]: OBJC_DEBUG_UNLOAD: warn about poorly-behaving bundles when unloaded
objc[13184]: OBJC_DEBUG_FRAGILE_SUPERCLASSES: warn about subclasses that may have been broken by subsequent changes to superclasses
objc[13184]: OBJC_DEBUG_FINALIZERS: warn about classes that implement -dealloc but not -finalize
objc[13184]: OBJC_DEBUG_NIL_SYNC: warn about @synchronized(nil), which does no synchronization
objc[13184]: OBJC_USE_INTERNAL_ZONE: allocate runtime data in a dedicated malloc zone
objc[13184]: OBJC_ALLOW_INTERPOSING: allow function interposing of objc_msgSend()
objc[13184]: OBJC_DISABLE_GC: force GC OFF, even if the executable wants it on