Garbage-Collected Types

JavaScriptCore has an automatic garbage-collector that scans the stack to see if a JavaScript value has any active references. When no references are found, the value will be collected (freed).

JSValueRef and JSObjectRef Types

Both JSValueRef and JSObjectRef are garbage-collected types-- if they go out of scope on the stack and are not stored in a global JavaScript object, they will be marked for collection.

Storing Values on the Heap

If you store JSValueRef or JSObjectRef on a static global or on the heap, the GC may inadvertently free these objects potentially causing memory corruption / crashes. To prevent this you should use JSValueProtect() and JSValueUnprotect() to keep them alive.

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