Two coupled changes that unblock the uikit_register_classes
migration:
1) M1.2 A.3 — body's 'self' is the Obj-C id (opaque), NOT the
state struct. Matches Apple's ObjC semantics where 'self' IS
the object. Cocoa idiom 'xx self → id' works at runtime calls
(addObserver:, etc.); previously the trampoline replaced
'self' with the state-struct pointer, breaking any runtime
call that expected an id.
'*Self' substitution in resolveTypeWithBindings now points at
foreignClassStructType(fcd) — the opaque class stub — instead
of objcDefinedStateStructType(fcd).
'self.field' access on a sx-defined class instance field is
rewritten by lowerFieldAccess to go through the __sx_state
ivar:
state = object_getIvar(self, load(__<Cls>_state_ivar))
val = struct_gep(state, field_idx) → load
Both read (lowerFieldAccess) and write (lowerAssignment) take
this path. Compound ops (+=, -=, etc.) are supported via
storeOrCompound. The lookup is filtered: skip property fields
(those still go through the M2.2 msgSend getter/setter
dispatch) and foreign classes (no state).
New helpers in lower.zig:
- lookupObjcDefinedStateFieldOnPointer — match check.
- lowerObjcDefinedStateForObj — emit the object_getIvar +
ivar-global-load idiom (shared between read + write paths).
- lowerObjcDefinedStateFieldRead — the load path.
Also moved the @llvm.global_ctors registration out of the
sx-defined class-pair init constructor — global_ctors fires
DURING dyld's framework load, before UIKit registers its Obj-C
classes. objc_getClass("UIResponder") returned null, super
was null, objc_registerClassPair crashed. main's entry block
is post-framework-load but pre-user-code — exactly the right
window. New helper injectCtorIntoMain.
2) M3.1 — SxAppDelegate migrated to declarative #objc_class.
uikit_register_classes' hand-rolled objc_allocateClassPair +
class_addMethod for SxAppDelegate is gone; the compiler
synthesises the class at module init. The method bodies
forward to the existing legacy IMP free functions
(uikit_did_finish_launching, uikit_keyboard_will_change_frame)
so we don't have to inline 70+ lines of keyboard-frame logic
right now.
Also adds UIResponder foreign-class declaration and chains
UIView / UITextField to it via #extends UIResponder so the
methods that previously lived on UITextField directly
(becomeFirstResponder etc.) move to their proper home.
Chess on iOS-sim: board renders, full state intact. 183 example
tests + zig build test green.