fix: check buf in drop_slow

discord9 · discord9 · commit 9ed51374125b · 2023-04-17T22:03:55.000+08:00
diff --git a/Lib/test/test_ordered_dict.py b/Lib/test/test_ordered_dict.py
@@ -665,8 +665,6 @@ class A:
         r = weakref.ref(A)
         del A
         gc.collect()
-        # TODO: RUSTPYTHON, Need to fix this: somehow after del A, it takes two call to `gc.collect()`
-        # for gc to realize a loop is there and to be collected
         self.assertIsNone(r())
 
     # TODO: RUSTPYTHON
diff --git a/vm/src/object/core.rs b/vm/src/object/core.rs
@@ -940,24 +940,39 @@ impl PyObject {
     }
 
     /// Can only be called when ref_count has dropped to zero. `ptr` must be valid, it run __del__ then drop&dealloc
-    pub(in crate::object) unsafe fn drop_slow(ptr: NonNull<PyObject>) -> bool {
+    pub(in crate::object) unsafe fn drop_slow(ptr: NonNull<PyObject>) {
         if let Err(()) = ptr.as_ref().drop_slow_inner() {
             // abort drop for whatever reason
-            return false;
+            return;
         }
 
         #[cfg(feature = "gc_bacon")]
-        if !ptr.as_ref().header().check_set_drop_dealloc() {
-            return false;
+        {
+            let zelf = ptr.as_ref();
+            // if is buffered by run `drop_slow_inner`, then drop only here and early return
+            if zelf.header().buffered() {
+                if zelf.header().check_set_drop_only() {
+                    Self::drop_only(ptr);
+                } else {
+                    panic!("Should be able to drop only for {:?}", zelf.header())
+                }
+                return;
+            }
+            if !ptr.as_ref().header().check_set_drop_dealloc() {
+                unreachable!(
+                    "Should be able to drop_dealloc for {:?}",
+                    ptr.as_ref().header()
+                )
+            }
         }
+
         #[cfg(debug_assertions)]
         {
             *ptr.as_ref().0.is_drop.lock() = true;
         }
         let drop_dealloc = ptr.as_ref().0.vtable.drop_dealloc;
         // call drop only when there are no references in scope - stacked borrows stuff
         drop_dealloc(ptr.as_ptr());
-        true
     }
 
     /// # Safety
diff --git a/vm/src/object/gc/object.rs b/vm/src/object/gc/object.rs
@@ -175,7 +175,14 @@ impl PyObject {
 
         Self::drop_clr_wr(ptr)
     }
+    /// call `drop_only` in vtable
+    pub(in crate::object) unsafe fn drop_only(ptr: NonNull<PyObject>) {
+        let zelf = ptr.as_ref();
+        // not set PyInner's is_drop because still havn't dealloc
+        let drop_only = zelf.0.vtable.drop_only;
 
+        drop_only(ptr.as_ptr());
+    }
     pub(in crate::object) unsafe fn dealloc_only(ptr: NonNull<PyObject>) -> bool {
         // can't check for if is a alive PyWeak here because already dropped payload
         #[cfg(feature = "gc_bacon")]
