backup

Author: youknowone

crates/vm/src/builtins/type.rs

@@ -438,8 +438,10 @@ impl PyType {
         }
         debug_assert!(
             slots.basicsize >= base.slots.basicsize,
-            "subclass basicsize ({}) must be >= base basicsize ({})",
+            "subclass {} basicsize ({}) must be >= base {} basicsize ({}). did you forget to add base payload as first field of subtype payload?",
+            slots.name,
             slots.basicsize,
+            base.slots.name,
             base.slots.basicsize
         );
 
@@ -500,7 +502,7 @@ impl PyType {
         }
         debug_assert!(
             slots.basicsize >= base.slots.basicsize,
-            "subclass {} basicsize ({}) must be >= base {} basicsize ({})",
+            "subclass {} basicsize ({}) must be >= base {} basicsize ({}). did you forget to add base payload as first field of subtype payload?",
             slots.name,
             slots.basicsize,
             base.slots.name,

crates/vm/src/stdlib/ctypes/pointer.rs

@@ -5,6 +5,7 @@ use crate::Py;
 use crate::builtins::{PyType, PyTypeRef};
 use crate::protocol::PyNumberMethods;
 use crate::stdlib::ctypes::PyCData;
+use crate::stdlib::ctypes::base::CDataObject;
 use crate::types::{AsNumber, Constructor};
 use crate::{AsObject, PyObjectRef, PyPayload, PyResult, VirtualMachine};
 
@@ -67,9 +68,20 @@ impl AsNumber for PyCPointerType {
 )]
 #[derive(Debug)]
 pub struct PyCPointer {
+    #[allow(dead_code)]
+    base: PyCData,
     contents: PyRwLock<PyObjectRef>,
 }
 
+impl PyCPointer {
+    fn make_base() -> PyCData {
+        let stg_info = StgInfo::new(std::mem::size_of::<usize>(), std::mem::align_of::<usize>());
+        PyCData {
+            cdata: PyRwLock::new(CDataObject::from_stg_info(&stg_info)),
+        }
+    }
+}
+
 impl Constructor for PyCPointer {
     type Args = (crate::function::OptionalArg<PyObjectRef>,);
 
@@ -79,6 +91,7 @@ impl Constructor for PyCPointer {
 
         // Create a new PyCPointer instance with the provided value
         Ok(PyCPointer {
+            base: Self::make_base(),
             contents: PyRwLock::new(initial_contents),
         })
     }
@@ -122,6 +135,7 @@ impl PyCPointer {
         }
         // Pointer just stores the address value
         let payload = PyCPointer {
+            base: Self::make_base(),
             contents: PyRwLock::new(vm.ctx.new_int(address).into()),
         };
         payload.into_ref_with_type(vm, cls).map(Into::into)
@@ -165,6 +179,7 @@ impl PyCPointer {
         let ptr_val = usize::from_ne_bytes(ptr_bytes.try_into().expect("size is checked above"));
 
         let payload = PyCPointer {
+            base: Self::make_base(),
             contents: PyRwLock::new(vm.ctx.new_int(ptr_val).into()),
         };
         payload.into_ref_with_type(vm, cls).map(Into::into)
@@ -200,6 +215,7 @@ impl PyCPointer {
         let ptr_val = usize::from_ne_bytes(ptr_bytes.try_into().expect("size is checked above"));
 
         let payload = PyCPointer {
+            base: Self::make_base(),
             contents: PyRwLock::new(vm.ctx.new_int(ptr_val).into()),
         };
         payload.into_ref_with_type(vm, cls).map(Into::into)
@@ -254,6 +270,7 @@ impl PyCPointer {
 
         // For pointer types, we return a pointer to the symbol address
         let payload = PyCPointer {
+            base: Self::make_base(),
             contents: PyRwLock::new(vm.ctx.new_int(symbol_address).into()),
         };
         payload.into_ref_with_type(vm, cls).map(Into::into)