pyo3 0.20, Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED

Cargo.toml

@@ -59,7 +59,7 @@ encoding_rs = { version = "0.8", default_features = false }
 itoa = { version = "1", default_features = false }
 itoap = { version = "1", features = ["std", "simd"] }
 once_cell = { version = "1", default_features = false, features = ["race"] }
-pyo3-ffi = { version = "^0.19.2", default_features = false, features = ["extension-module"]}
+pyo3-ffi = { version = "^0.20", default_features = false, features = ["extension-module"]}
 ryu = { version = "1", default_features = false }
 serde = { version = "1", default_features = false }
 serde_json = { version = "1", default_features = false, features = ["std", "float_roundtrip"] }
@@ -68,7 +68,7 @@ smallvec = { version = "^1.11", default_features = false, features = ["union", "
 
 [build-dependencies]
 cc = { version = "1" }
-pyo3-build-config = { version = "^0.19.2" }
+pyo3-build-config = { version = "^0.20" }
 version_check = { version = "0.9" }
 
 [profile.dev]

README.md

@@ -35,7 +35,8 @@ file-like objects
 orjson supports CPython 3.8, 3.9, 3.10, 3.11, and 3.12. It distributes
 amd64/x86_64, aarch64/armv8, arm7, POWER/ppc64le, and s390x wheels for Linux,
 amd64 and aarch64 wheels for macOS, and amd64 and i686/x86 wheels for Windows.
-orjson  does not support PyPy. Releases follow semantic versioning and
+orjson does not and will not support PyPy. orjson does not and will not
+support PEP 554 subinterpreters. Releases follow semantic versioning and
 serializing a new object type without an opt-in flag is considered a
 breaking change.
 
@@ -1177,10 +1178,6 @@ level above this.
 
 No. `bytes` is the correct type for a serialized blob.
 
-### Will it support PyPy?
-
-Probably not.
-
 ## Packaging
 
 To package orjson requires at least [Rust](https://www.rust-lang.org/) 1.65

src/ffi/mod.rs

@@ -3,8 +3,6 @@
 mod buffer;
 mod bytes;
 mod fragment;
-#[cfg(Py_3_12)]
-mod immortal;
 mod list;
 mod long;
 #[cfg(feature = "yyjson")]
@@ -13,7 +11,5 @@ pub mod yyjson;
 pub use buffer::*;
 pub use bytes::*;
 pub use fragment::{orjson_fragmenttype_new, Fragment};
-#[cfg(Py_3_12)]
-pub use immortal::_Py_IsImmortal;
 pub use list::PyListIter;
 pub use long::{pylong_is_unsigned, pylong_is_zero};

src/lib.rs

@@ -143,16 +143,26 @@ pub unsafe extern "C" fn orjson_init_exec(mptr: *mut PyObject) -> c_int {
     0
 }
 
+#[cfg(not(Py_3_12))]
+const PYMODULEDEF_LEN: usize = 2;
+#[cfg(Py_3_12)]
+const PYMODULEDEF_LEN: usize = 3;
+
 #[allow(non_snake_case)]
 #[no_mangle]
 #[cold]
 #[cfg_attr(feature = "optimize", optimize(size))]
 pub unsafe extern "C" fn PyInit_orjson() -> *mut PyModuleDef {
-    let mod_slots: Box<[PyModuleDef_Slot; 2]> = Box::new([
+    let mod_slots: Box<[PyModuleDef_Slot; PYMODULEDEF_LEN]> = Box::new([
         PyModuleDef_Slot {
             slot: Py_mod_exec,
             value: orjson_init_exec as *mut c_void,
         },
+        #[cfg(Py_3_12)]
+        PyModuleDef_Slot {
+            slot: Py_mod_multiple_interpreters,
+            value: Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED,
+        },
         PyModuleDef_Slot {
             slot: 0,
             value: null_mut(),

src/util.rs

@@ -86,7 +86,7 @@ macro_rules! str_from_slice {
 macro_rules! reverse_pydict_incref {
     ($op:expr) => {
         unsafe {
-            if crate::ffi::_Py_IsImmortal($op) == 0 {
+            if pyo3_ffi::_Py_IsImmortal($op) == 0 {
                 debug_assert!(ffi!(Py_REFCNT($op)) >= 2);
                 (*$op).ob_refcnt.ob_refcnt -= 1;
             }