More destruction rules following code.

TODO.md

@@ -22,7 +22,7 @@
 - settle onDestroy/destroy naming
 - clean up Windows lifetiming code
 - forbid free(NULL) to check for bugs
-- figure out how to do the parent on destroy check for uiStack
+- figure out how to do the parent on destroy check for children of a uiStack without a parent in and of itself
 
 ultimately:
 - make everything vtable-based

darwin/parent.m

@@ -27,6 +27,8 @@ uiLogObjCClassAllocations
 - (void)uipDestroyMainControl
 {
 	if (self->mainControl != NULL) {
+		// we have to do this before we can destroy controls
+		uiControlSetParent(p->mainControl, NULL);
 		uiControlDestroy(self->mainControl);
 		self->mainControl = NULL;
 	}

stack.c

@@ -33,6 +33,8 @@ static void stackDestroy(uiControl *c)
 	stack *s = (stack *) c;
 	uintmax_t i;
 
+	if (s->parent != NULL)
+		complain("attempt to destroy a uiControl at %p while it still has a parent %p", c, s->parent);
 	for (i = 0; i < s->len; i++)
 		uiControlDestroy(s->controls[i].c);
 	uiFree(s->controls);

unix/parent.c

@@ -146,6 +146,8 @@ static void parentDestroy(uiParent *pp)
 
 	// first, destroy the main control
 	if (p->mainControl != NULL) {
+		// we have to do this before we can destroy controls
+		uiControlSetParent(p->mainControl, NULL);
 		uiControlDestroy(p->mainControl);
 		p->mainControl = NULL;
 	}

windows/parent.c

@@ -235,6 +235,8 @@ static void parentDestroy(uiParent *pp)
 
 	// first destroy the main control, if any
 	if (p->mainControl != NULL) {
+		// we have to do this before we can destroy controls
+		uiControlSetParent(p->mainControl, NULL);
 		uiControlDestroy(p->mainControl);
 		p->mainControl = NULL;
 	}