[3.13] gh-119821: Support non-dict globals in LOAD_FROM_DICT_OR_GLOBALS (#119822...

dSupport non-dict globals in LOAD_FROM_DICT_OR_GLOBALS

The implementation basically copies LOAD_GLOBAL. Possibly it could be deduplicated,
but that seems like it may get hairy since the two operations have different operands.

This is important to fix in 3.14 for PEP 649, but it's a bug in earlier versions too,
and we should backport to 3.13 and 3.12 if possible.

(cherry picked from commit 80a4e3899420faaa012c82b4e82cdb6675a6a944)

diff --git a/Include/internal/pycore_opcode_metadata.h b/Include/internal/pycore_opcode_metadata.h
index 665b8627dfcc5244112b712dabdd96e85989b7c8..5b0d8dfd1b0b9749c4b1176d7c9a0907759a608b 100644 (file)
--- a/Include/internal/pycore_opcode_metadata.h
+++ b/Include/internal/pycore_opcode_metadata.h
@@ -1299,7 +1299,6 @@ _PyOpcode_macro_expansion[256] = {
     [LOAD_FAST_CHECK] = { .nuops = 1, .uops = { { _LOAD_FAST_CHECK, 0, 0 } } },
     [LOAD_FAST_LOAD_FAST] = { .nuops = 2, .uops = { { _LOAD_FAST, 5, 0 }, { _LOAD_FAST, 6, 0 } } },
     [LOAD_FROM_DICT_OR_DEREF] = { .nuops = 1, .uops = { { _LOAD_FROM_DICT_OR_DEREF, 0, 0 } } },
-    [LOAD_FROM_DICT_OR_GLOBALS] = { .nuops = 1, .uops = { { _LOAD_FROM_DICT_OR_GLOBALS, 0, 0 } } },
     [LOAD_GLOBAL] = { .nuops = 1, .uops = { { _LOAD_GLOBAL, 0, 0 } } },
     [LOAD_GLOBAL_BUILTIN] = { .nuops = 3, .uops = { { _GUARD_GLOBALS_VERSION, 1, 1 }, { _GUARD_BUILTINS_VERSION, 1, 2 }, { _LOAD_GLOBAL_BUILTINS, 1, 3 } } },
     [LOAD_GLOBAL_MODULE] = { .nuops = 2, .uops = { { _GUARD_GLOBALS_VERSION, 1, 1 }, { _LOAD_GLOBAL_MODULE, 1, 3 } } },

diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
index 470e95e2b3b041584e199c4044db67c8e3d3fdba..bc0ba16e24fe9880c5ad462d26c0bf3746704fae 100644 (file)
--- a/Include/internal/pycore_uop_metadata.h
+++ b/Include/internal/pycore_uop_metadata.h
@@ -107,7 +107,6 @@ const uint16_t _PyUop_Flags[MAX_UOP_ID+1] = {
     [_STORE_GLOBAL] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
     [_DELETE_GLOBAL] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ERROR_NO_POP_FLAG | HAS_ESCAPES_FLAG,
     [_LOAD_LOCALS] = HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
-    [_LOAD_FROM_DICT_OR_GLOBALS] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ERROR_NO_POP_FLAG | HAS_ESCAPES_FLAG,
     [_LOAD_GLOBAL] = HAS_ARG_FLAG | HAS_NAME_FLAG | HAS_ERROR_FLAG | HAS_ESCAPES_FLAG,
     [_GUARD_GLOBALS_VERSION] = HAS_DEOPT_FLAG,
     [_GUARD_BUILTINS_VERSION] = HAS_DEOPT_FLAG,
@@ -438,7 +437,6 @@ const char *const _PyOpcode_uop_name[MAX_UOP_ID+1] = {
     [_LOAD_FAST_CHECK] = "_LOAD_FAST_CHECK",
     [_LOAD_FAST_LOAD_FAST] = "_LOAD_FAST_LOAD_FAST",
     [_LOAD_FROM_DICT_OR_DEREF] = "_LOAD_FROM_DICT_OR_DEREF",
-    [_LOAD_FROM_DICT_OR_GLOBALS] = "_LOAD_FROM_DICT_OR_GLOBALS",
     [_LOAD_GLOBAL] = "_LOAD_GLOBAL",
     [_LOAD_GLOBAL_BUILTINS] = "_LOAD_GLOBAL_BUILTINS",
     [_LOAD_GLOBAL_MODULE] = "_LOAD_GLOBAL_MODULE",
@@ -690,8 +688,6 @@ int _PyUop_num_popped(int opcode, int oparg)
             return 0;
         case _LOAD_LOCALS:
             return 0;
-        case _LOAD_FROM_DICT_OR_GLOBALS:
-            return 1;
         case _LOAD_GLOBAL:
             return 0;
         case _GUARD_GLOBALS_VERSION:

diff --git a/Lib/test/test_type_aliases.py b/Lib/test/test_type_aliases.py
index 9c325bc595f585a790e9aa805ac54a57cd7a428c..f8b395fdc8bb1d4552c3c92e9d9bc326ff29d79e 100644 (file)
--- a/Lib/test/test_type_aliases.py
+++ b/Lib/test/test_type_aliases.py
@@ -1,4 +1,5 @@
 import pickle
+import textwrap
 import types
 import unittest
 from test.support import check_syntax_error, run_code
@@ -328,3 +329,22 @@ class TypeAliasPickleTest(unittest.TestCase):
                 with self.subTest(thing=thing, proto=proto):
                     with self.assertRaises(pickle.PickleError):
                         pickle.dumps(thing, protocol=proto)
+
+
+class TypeParamsExoticGlobalsTest(unittest.TestCase):
+    def test_exec_with_unusual_globals(self):
+        class customdict(dict):
+            def __missing__(self, key):
+                return key
+
+        code = compile("type Alias = undefined", "test", "exec")
+        ns = customdict()
+        exec(code, ns)
+        Alias = ns["Alias"]
+        self.assertEqual(Alias.__value__, "undefined")
+
+        code = compile("class A: type Alias = undefined", "test", "exec")
+        ns = customdict()
+        exec(code, ns)
+        Alias = ns["A"].Alias
+        self.assertEqual(Alias.__value__, "undefined")

diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-05-30-23-01-00.gh-issue-119821.jPGfvt.rst b/Misc/NEWS.d/next/Core and Builtins/2024-05-30-23-01-00.gh-issue-119821.jPGfvt.rst
new file mode 100644 (file)
index 0000000..cc25eee
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-05-30-23-01-00.gh-issue-119821.jPGfvt.rst
@@ -0,0 +1,2 @@
+Fix execution of :ref:`annotation scopes <annotation-scopes>` within classes
+when ``globals`` is set to a non-dict. Patch by Jelle Zijlstra.

diff --git a/Python/bytecodes.c b/Python/bytecodes.c
index 8a6222c2bf0d77a3b3b6e1288c82f3678a18f6a6..0dc60bbbb6a57990b400d13c2f7bdcf5342a0e63 100644 (file)
--- a/Python/bytecodes.c
+++ b/Python/bytecodes.c
@@ -1375,18 +1375,35 @@ dummy_func(
                 ERROR_NO_POP();
             }
             if (v == NULL) {
-                if (PyDict_GetItemRef(GLOBALS(), name, &v) < 0) {
-                    ERROR_NO_POP();
-                }
-                if (v == NULL) {
-                    if (PyMapping_GetOptionalItem(BUILTINS(), name, &v) < 0) {
+                if (PyDict_CheckExact(GLOBALS())
+                    && PyDict_CheckExact(BUILTINS()))
+                {
+                    v = _PyDict_LoadGlobal((PyDictObject *)GLOBALS(),
+                                            (PyDictObject *)BUILTINS(),
+                                            name);
+                    if (v == NULL) {
+                        if (!_PyErr_Occurred(tstate)) {
+                            /* _PyDict_LoadGlobal() returns NULL without raising
+                            * an exception if the key doesn't exist */
+                            _PyEval_FormatExcCheckArg(tstate, PyExc_NameError,
+                                                    NAME_ERROR_MSG, name);
+                        }
                         ERROR_NO_POP();
                     }
+                }
+                else {
+                    /* Slow-path if globals or builtins is not a dict */
+                    /* namespace 1: globals */
+                    ERROR_IF(PyMapping_GetOptionalItem(GLOBALS(), name, &v) < 0, error);
                     if (v == NULL) {
-                        _PyEval_FormatExcCheckArg(
-                                    tstate, PyExc_NameError,
-                                    NAME_ERROR_MSG, name);
-                        ERROR_NO_POP();
+                        /* namespace 2: builtins */
+                        ERROR_IF(PyMapping_GetOptionalItem(BUILTINS(), name, &v) < 0, error);
+                        if (v == NULL) {
+                            _PyEval_FormatExcCheckArg(
+                                        tstate, PyExc_NameError,
+                                        NAME_ERROR_MSG, name);
+                            ERROR_IF(true, error);
+                        }
                     }
                 }
             }

diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
index 4699c8efebedc99bcfdbaa6a87b43ecce796cde7..4e0f73f7e23a0a801b0642f04d8f55cf0f5882ad 100644 (file)
--- a/Python/executor_cases.c.h
+++ b/Python/executor_cases.c.h
@@ -1394,35 +1394,7 @@
             break;
         }
 
-        case _LOAD_FROM_DICT_OR_GLOBALS: {
-            PyObject *mod_or_class_dict;
-            PyObject *v;
-            oparg = CURRENT_OPARG();
-            mod_or_class_dict = stack_pointer[-1];
-            PyObject *name = GETITEM(FRAME_CO_NAMES, oparg);
-            if (PyMapping_GetOptionalItem(mod_or_class_dict, name, &v) < 0) {
-                JUMP_TO_ERROR();
-            }
-            if (v == NULL) {
-                if (PyDict_GetItemRef(GLOBALS(), name, &v) < 0) {
-                    JUMP_TO_ERROR();
-                }
-                if (v == NULL) {
-                    if (PyMapping_GetOptionalItem(BUILTINS(), name, &v) < 0) {
-                        JUMP_TO_ERROR();
-                    }
-                    if (v == NULL) {
-                        _PyEval_FormatExcCheckArg(
-                            tstate, PyExc_NameError,
-                            NAME_ERROR_MSG, name);
-                        JUMP_TO_ERROR();
-                    }
-                }
-            }
-            Py_DECREF(mod_or_class_dict);
-            stack_pointer[-1] = v;
-            break;
-        }
+        /* _LOAD_FROM_DICT_OR_GLOBALS is not a viable micro-op for tier 2 because it has both popping and not-popping errors */
 
         /* _LOAD_NAME is not a viable micro-op for tier 2 because it has both popping and not-popping errors */
 

diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h
index 32d5b8b1c1d93c3e73a3c49cc5ba69002e1147e1..ace91a3ca9b6245e1cf0b6e6540c7ef1a5f4b508 100644 (file)
--- a/Python/generated_cases.c.h
+++ b/Python/generated_cases.c.h
@@ -4381,18 +4381,35 @@
                 goto error;
             }
             if (v == NULL) {
-                if (PyDict_GetItemRef(GLOBALS(), name, &v) < 0) {
-                    goto error;
-                }
-                if (v == NULL) {
-                    if (PyMapping_GetOptionalItem(BUILTINS(), name, &v) < 0) {
+                if (PyDict_CheckExact(GLOBALS())
+                    && PyDict_CheckExact(BUILTINS()))
+                {
+                    v = _PyDict_LoadGlobal((PyDictObject *)GLOBALS(),
+                        (PyDictObject *)BUILTINS(),
+                        name);
+                    if (v == NULL) {
+                        if (!_PyErr_Occurred(tstate)) {
+                            /* _PyDict_LoadGlobal() returns NULL without raising
+                             * an exception if the key doesn't exist */
+                            _PyEval_FormatExcCheckArg(tstate, PyExc_NameError,
+                                NAME_ERROR_MSG, name);
+                        }
                         goto error;
                     }
+                }
+                else {
+                    /* Slow-path if globals or builtins is not a dict */
+                    /* namespace 1: globals */
+                    if (PyMapping_GetOptionalItem(GLOBALS(), name, &v) < 0) goto pop_1_error;
                     if (v == NULL) {
-                        _PyEval_FormatExcCheckArg(
-                            tstate, PyExc_NameError,
-                            NAME_ERROR_MSG, name);
-                        goto error;
+                        /* namespace 2: builtins */
+                        if (PyMapping_GetOptionalItem(BUILTINS(), name, &v) < 0) goto pop_1_error;
+                        if (v == NULL) {
+                            _PyEval_FormatExcCheckArg(
+                                tstate, PyExc_NameError,
+                                NAME_ERROR_MSG, name);
+                            if (true) goto pop_1_error;
+                        }
                     }
                 }
             }

diff --git a/Python/optimizer_cases.c.h b/Python/optimizer_cases.c.h
index 2a4efd73d794df5fed8dcb9f06c20385ad7a8615..6c2480d4fdfe891e781df49075ba2193bdc3366c 100644 (file)
--- a/Python/optimizer_cases.c.h
+++ b/Python/optimizer_cases.c.h
@@ -815,13 +815,7 @@
             break;
         }
 
-        case _LOAD_FROM_DICT_OR_GLOBALS: {
-            _Py_UopsSymbol *v;
-            v = sym_new_not_null(ctx);
-            if (v == NULL) goto out_of_space;
-            stack_pointer[-1] = v;
-            break;
-        }
+        /* _LOAD_FROM_DICT_OR_GLOBALS is not a viable micro-op for tier 2 */
 
         /* _LOAD_NAME is not a viable micro-op for tier 2 */