From 4deca7653e11c621d9444378e009a6fda9e3974c Mon Sep 17 00:00:00 2001 From: Mark Shannon Date: Tue, 6 Jan 2026 15:34:42 +0000 Subject: [PATCH 1/2] Conform to spec for generator expressions while supporting virtual iterators * Moves the `GET_ITER` instruction into the generator function preamble. This means the the iterable is converted into an iterator during generator creation, as documented, but keeps it in the same code object allowing optimization. --- Include/internal/pycore_flowgraph.h | 2 +- .../internal/pycore_instruction_sequence.h | 1 + Include/internal/pycore_magic_number.h | 3 +- Lib/test/test_compile.py | 2 +- Lib/test/test_dis.py | 8 +- Lib/test/test_generators.py | 34 +++++---- Python/bytecodes.c | 5 +- Python/codegen.c | 76 +++++++++++++++---- Python/compile.c | 4 +- Python/executor_cases.c.h | 3 +- Python/flowgraph.c | 50 +++--------- Python/generated_cases.c.h | 3 +- Python/instruction_sequence.c | 7 ++ 13 files changed, 112 insertions(+), 86 deletions(-) diff --git a/Include/internal/pycore_flowgraph.h b/Include/internal/pycore_flowgraph.h index 5043260d2fd99f..fc3ae6b369c54c 100644 --- a/Include/internal/pycore_flowgraph.h +++ b/Include/internal/pycore_flowgraph.h @@ -27,7 +27,7 @@ int _PyCfg_OptimizeCodeUnit(struct _PyCfgBuilder *g, PyObject *consts, PyObject struct _PyCfgBuilder* _PyCfg_FromInstructionSequence(_PyInstructionSequence *seq); int _PyCfg_ToInstructionSequence(struct _PyCfgBuilder *g, _PyInstructionSequence *seq); int _PyCfg_OptimizedCfgToInstructionSequence(struct _PyCfgBuilder *g, _PyCompile_CodeUnitMetadata *umd, - int code_flags, int *stackdepth, int *nlocalsplus, + int *stackdepth, int *nlocalsplus, _PyInstructionSequence *seq); PyCodeObject * diff --git a/Include/internal/pycore_instruction_sequence.h b/Include/internal/pycore_instruction_sequence.h index b5c927735374be..6257b771fd9539 100644 --- a/Include/internal/pycore_instruction_sequence.h +++ b/Include/internal/pycore_instruction_sequence.h @@ -73,6 +73,7 @@ int _PyInstructionSequence_SetAnnotationsCode(_PyInstructionSequence *seq, _PyInstructionSequence *annotations); int _PyInstructionSequence_AddNested(_PyInstructionSequence *seq, _PyInstructionSequence *nested); void PyInstructionSequence_Fini(_PyInstructionSequence *seq); +_PyInstruction _PyInstructionSequence_GetInstruction(_PyInstructionSequence *seq, int pos); extern PyTypeObject _PyInstructionSequence_Type; #define _PyInstructionSequence_Check(v) Py_IS_TYPE((v), &_PyInstructionSequence_Type) diff --git a/Include/internal/pycore_magic_number.h b/Include/internal/pycore_magic_number.h index eb2e03829e28e1..919a2ec0d1aa9e 100644 --- a/Include/internal/pycore_magic_number.h +++ b/Include/internal/pycore_magic_number.h @@ -290,6 +290,7 @@ Known values: Python 3.15a4 3657 (Add BINARY_OP_SUBSCR_USTR_INT) Python 3.15a4 3658 (Optimize bytecode for list/set called on genexp) Python 3.15a4 3659 (Add CALL_FUNCTION_EX specialization) + Python 3.15a4 3660 (Change generator preamble code) Python 3.16 will start with 3700 @@ -303,7 +304,7 @@ PC/launcher.c must also be updated. */ -#define PYC_MAGIC_NUMBER 3659 +#define PYC_MAGIC_NUMBER 3660 /* This is equivalent to converting PYC_MAGIC_NUMBER to 2 bytes (little-endian) and then appending b'\r\n'. */ #define PYC_MAGIC_NUMBER_TOKEN \ diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py index fa611f480d60fd..591332cb5b9bcf 100644 --- a/Lib/test/test_compile.py +++ b/Lib/test/test_compile.py @@ -1298,7 +1298,7 @@ def return_genexp(): x in y) - genexp_lines = [0, 4, 2, 0, 4] + genexp_lines = [4, 0, 4, 2, 0, 4] genexp_code = return_genexp.__code__.co_consts[0] code_lines = self.get_code_lines(genexp_code) diff --git a/Lib/test/test_dis.py b/Lib/test/test_dis.py index 902bcdd196ec93..8529afaa3f5370 100644 --- a/Lib/test/test_dis.py +++ b/Lib/test/test_dis.py @@ -875,11 +875,11 @@ def foo(x): Disassembly of at 0x..., file "%s", line %d>: -- COPY_FREE_VARS 1 -%4d RETURN_GENERATOR +%4d LOAD_FAST 0 (.0) + GET_ITER + RETURN_GENERATOR POP_TOP L1: RESUME 0 - LOAD_FAST 0 (.0) - GET_ITER L2: FOR_ITER 14 (to L3) STORE_FAST 1 (z) LOAD_DEREF 2 (x) @@ -897,7 +897,7 @@ def foo(x): -- L4: CALL_INTRINSIC_1 3 (INTRINSIC_STOPITERATION_ERROR) RERAISE 1 ExceptionTable: - L1 to L4 -> L4 [0] lasti + L1 to L4 -> L4 [2] lasti """ % (dis_nested_1, __file__, _h.__code__.co_firstlineno + 3, diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py index 6643c396edf2be..c181da2e349915 100644 --- a/Lib/test/test_generators.py +++ b/Lib/test/test_generators.py @@ -357,21 +357,25 @@ def gen(it): yield x return gen(range(10)) - def process_tests(self, get_generator): - for obj in self.iterables: - g_obj = get_generator(obj) - with self.subTest(g_obj=g_obj, obj=obj): - self.assertListEqual(list(g_obj), list(obj)) + def process_tests(self, get_generator, changes_iterable): + if changes_iterable: + for obj in self.iterables: + g_obj = get_generator(obj) + with self.subTest(g_obj=g_obj, obj=obj): + self.assertListEqual(list(g_obj), list(obj)) - g_iter = get_generator(iter(obj)) - with self.subTest(g_iter=g_iter, obj=obj): - self.assertListEqual(list(g_iter), list(obj)) + g_iter = get_generator(iter(obj)) + with self.subTest(g_iter=g_iter, obj=obj): + self.assertListEqual(list(g_iter), list(obj)) err_regex = "'.*' object is not iterable" for obj in self.non_iterables: g_obj = get_generator(obj) with self.subTest(g_obj=g_obj): - self.assertRaisesRegex(TypeError, err_regex, list, g_obj) + if changes_iterable: + self.assertRaisesRegex(TypeError, err_regex, list, g_obj) + else: + next(g_obj) def test_modify_f_locals(self): def modify_f_locals(g, local, obj): @@ -384,22 +388,22 @@ def get_generator_genexpr(obj): def get_generator_genfunc(obj): return modify_f_locals(self.genfunc(), 'it', obj) - self.process_tests(get_generator_genexpr) - self.process_tests(get_generator_genfunc) + self.process_tests(get_generator_genexpr, False) + self.process_tests(get_generator_genfunc, True) def test_new_gen_from_gi_code(self): def new_gen_from_gi_code(g, obj): generator_func = types.FunctionType(g.gi_code, {}) return generator_func(obj) - def get_generator_genexpr(obj): - return new_gen_from_gi_code(self.genexpr(), obj) + for obj in self.non_iterables: + with self.assertRaises(TypeError): + new_gen_from_gi_code(self.genexpr(), obj) def get_generator_genfunc(obj): return new_gen_from_gi_code(self.genfunc(), obj) - self.process_tests(get_generator_genexpr) - self.process_tests(get_generator_genfunc) + self.process_tests(get_generator_genfunc, True) class ExceptionTest(unittest.TestCase): diff --git a/Python/bytecodes.c b/Python/bytecodes.c index 5e5e818b9d3f55..0b20f8fc114c20 100644 --- a/Python/bytecodes.c +++ b/Python/bytecodes.c @@ -3166,14 +3166,15 @@ dummy_func( #ifdef Py_STATS _Py_GatherStats_GetIter(iterable); #endif - /* before: [obj]; after [getiter(obj)] */ PyTypeObject *tp = PyStackRef_TYPE(iterable); if (tp == &PyTuple_Type || tp == &PyList_Type) { + /* Leave iterable on stack and pushed tagged 0 */ iter = iterable; DEAD(iterable); index_or_null = PyStackRef_TagInt(0); } else { + /* Pop iterable, and push iterator then NULL */ PyObject *iter_o = PyObject_GetIter(PyStackRef_AsPyObjectBorrow(iterable)); PyStackRef_CLOSE(iterable); ERROR_IF(iter_o == NULL); @@ -5010,7 +5011,7 @@ dummy_func( PyFunctionObject *func = (PyFunctionObject *)PyStackRef_AsPyObjectBorrow(frame->f_funcobj); PyGenObject *gen = (PyGenObject *)_Py_MakeCoro(func); ERROR_IF(gen == NULL); - assert(STACK_LEVEL() == 0); + assert(STACK_LEVEL() <= 2); SAVE_STACK(); _PyInterpreterFrame *gen_frame = &gen->gi_iframe; frame->instr_ptr++; diff --git a/Python/codegen.c b/Python/codegen.c index acd8d84bc9ec6d..142b94e6425300 100644 --- a/Python/codegen.c +++ b/Python/codegen.c @@ -227,19 +227,25 @@ static int codegen_call_helper(compiler *c, location loc, static int codegen_try_except(compiler *, stmt_ty); static int codegen_try_star_except(compiler *, stmt_ty); +typedef enum { + ITERABLE_IN_LOCAL = 0, + ITERABLE_ON_STACK = 1, + ITERATOR_ON_STACK = 2, +} IterStackState; + static int codegen_sync_comprehension_generator( compiler *c, location loc, asdl_comprehension_seq *generators, int gen_index, int depth, expr_ty elt, expr_ty val, int type, - int iter_on_stack); + IterStackState iter_on_stack); static int codegen_async_comprehension_generator( compiler *c, location loc, asdl_comprehension_seq *generators, int gen_index, int depth, expr_ty elt, expr_ty val, int type, - int iter_on_stack); + IterStackState iter_on_stack); static int codegen_pattern(compiler *, pattern_ty, pattern_context *); static int codegen_match(compiler *, stmt_ty); @@ -665,6 +671,18 @@ codegen_enter_scope(compiler *c, identifier name, int scope_type, if (scope_type == COMPILE_SCOPE_MODULE) { loc.lineno = 0; } + /* Add the generator prefix instructions. */ + + PySTEntryObject *ste = SYMTABLE_ENTRY(c); + if (ste->ste_coroutine || ste->ste_generator) { + /* Note that RETURN_GENERATOR + POP_TOP have a net stack effect + * of 0. This is because RETURN_GENERATOR pushes the generator + before returning. */ + location loc = LOCATION(lineno, lineno, -1, -1); + ADDOP(c, loc, RETURN_GENERATOR); + ADDOP(c, loc, POP_TOP); + } + ADDOP_I(c, loc, RESUME, RESUME_AT_FUNC_START); if (scope_type == COMPILE_SCOPE_MODULE) { ADDOP(c, loc, ANNOTATIONS_PLACEHOLDER); @@ -1187,10 +1205,15 @@ codegen_wrap_in_stopiteration_handler(compiler *c) { NEW_JUMP_TARGET_LABEL(c, handler); - /* Insert SETUP_CLEANUP at start */ + /* Insert SETUP_CLEANUP just before RESUME */ + instr_sequence *seq = INSTR_SEQUENCE(c); + int resume = 0; + while (_PyInstructionSequence_GetInstruction(seq, resume).i_opcode != RESUME) { + resume++; + } RETURN_IF_ERROR( _PyInstructionSequence_InsertInstruction( - INSTR_SEQUENCE(c), 0, + seq, resume, SETUP_CLEANUP, handler.id, NO_LOCATION)); ADDOP_LOAD_CONST(c, NO_LOCATION, Py_None); @@ -4401,7 +4424,7 @@ codegen_comprehension_generator(compiler *c, location loc, asdl_comprehension_seq *generators, int gen_index, int depth, expr_ty elt, expr_ty val, int type, - int iter_on_stack) + IterStackState iter_on_stack) { comprehension_ty gen; gen = (comprehension_ty)asdl_seq_GET(generators, gen_index); @@ -4421,7 +4444,7 @@ codegen_sync_comprehension_generator(compiler *c, location loc, asdl_comprehension_seq *generators, int gen_index, int depth, expr_ty elt, expr_ty val, int type, - int iter_on_stack) + IterStackState iter_on_stack) { /* generate code for the iterator, then each of the ifs, and then write to the element */ @@ -4433,7 +4456,7 @@ codegen_sync_comprehension_generator(compiler *c, location loc, comprehension_ty gen = (comprehension_ty)asdl_seq_GET(generators, gen_index); - if (!iter_on_stack) { + if (iter_on_stack == ITERABLE_IN_LOCAL) { if (gen_index == 0) { assert(METADATA(c)->u_argcount == 1); ADDOP_I(c, loc, LOAD_FAST, 0); @@ -4468,9 +4491,12 @@ codegen_sync_comprehension_generator(compiler *c, location loc, } if (IS_JUMP_TARGET_LABEL(start)) { - depth += 2; - ADDOP(c, LOC(gen->iter), GET_ITER); + if (iter_on_stack != ITERATOR_ON_STACK) { + ADDOP(c, LOC(gen->iter), GET_ITER); + depth += 1; + } USE_LABEL(c, start); + depth += 1; ADDOP_JUMP(c, LOC(gen->iter), FOR_ITER, anchor); } VISIT(c, expr, gen->target); @@ -4486,7 +4512,7 @@ codegen_sync_comprehension_generator(compiler *c, location loc, RETURN_IF_ERROR( codegen_comprehension_generator(c, loc, generators, gen_index, depth, - elt, val, type, 0)); + elt, val, type, ITERABLE_IN_LOCAL)); } location elt_loc = LOC(elt); @@ -4545,7 +4571,7 @@ codegen_async_comprehension_generator(compiler *c, location loc, asdl_comprehension_seq *generators, int gen_index, int depth, expr_ty elt, expr_ty val, int type, - int iter_on_stack) + IterStackState iter_on_stack) { NEW_JUMP_TARGET_LABEL(c, start); NEW_JUMP_TARGET_LABEL(c, send); @@ -4555,7 +4581,7 @@ codegen_async_comprehension_generator(compiler *c, location loc, comprehension_ty gen = (comprehension_ty)asdl_seq_GET(generators, gen_index); - if (!iter_on_stack) { + if (iter_on_stack == ITERABLE_IN_LOCAL) { if (gen_index == 0) { assert(METADATA(c)->u_argcount == 1); ADDOP_I(c, loc, LOAD_FAST, 0); @@ -4565,7 +4591,9 @@ codegen_async_comprehension_generator(compiler *c, location loc, VISIT(c, expr, gen->iter); } } - ADDOP(c, LOC(gen->iter), GET_AITER); + if (iter_on_stack != ITERATOR_ON_STACK) { + ADDOP(c, LOC(gen->iter), GET_AITER); + } USE_LABEL(c, start); /* Runtime will push a block here, so we need to account for that */ @@ -4795,11 +4823,13 @@ codegen_comprehension(compiler *c, expr_ty e, int type, location loc = LOC(e); outermost = (comprehension_ty) asdl_seq_GET(generators, 0); + IterStackState iter_state; if (is_inlined) { VISIT(c, expr, outermost->iter); if (push_inlined_comprehension_state(c, loc, entry, &inline_state)) { goto error; } + iter_state = ITERABLE_ON_STACK; } else { /* Receive outermost iter as an implicit argument */ @@ -4810,6 +4840,23 @@ codegen_comprehension(compiler *c, expr_ty e, int type, (void *)e, e->lineno, NULL, &umd) < 0) { goto error; } + if (type == COMP_GENEXP) { + /* Insert GET_ITER before RETURN_GENERATOR. + https://docs.python.org/3/reference/expressions.html#generator-expressions */ + RETURN_IF_ERROR( + _PyInstructionSequence_InsertInstruction( + INSTR_SEQUENCE(c), 0, + LOAD_FAST, 0, LOC(outermost->iter))); + RETURN_IF_ERROR( + _PyInstructionSequence_InsertInstruction( + INSTR_SEQUENCE(c), 1, + outermost->is_async ? GET_AITER : GET_ITER, + 0, LOC(outermost->iter))); + iter_state = ITERATOR_ON_STACK; + } + else { + iter_state = ITERABLE_IN_LOCAL; + } } Py_CLEAR(entry); @@ -4836,9 +4883,8 @@ codegen_comprehension(compiler *c, expr_ty e, int type, ADDOP_I(c, loc, SWAP, 2); } } - if (codegen_comprehension_generator(c, loc, generators, 0, 0, - elt, val, type, is_inlined) < 0) { + elt, val, type, iter_state) < 0) { goto error_in_scope; } diff --git a/Python/compile.c b/Python/compile.c index 1ab96a37f683f2..1f154004969f31 100644 --- a/Python/compile.c +++ b/Python/compile.c @@ -1443,7 +1443,7 @@ optimize_and_assemble_code_unit(struct compiler_unit *u, PyObject *const_cache, int stackdepth; int nlocalsplus; - if (_PyCfg_OptimizedCfgToInstructionSequence(g, &u->u_metadata, code_flags, + if (_PyCfg_OptimizedCfgToInstructionSequence(g, &u->u_metadata, &stackdepth, &nlocalsplus, &optimized_instrs) < 0) { goto error; @@ -1718,7 +1718,7 @@ _PyCompile_Assemble(_PyCompile_CodeUnitMetadata *umd, PyObject *filename, int code_flags = 0; int stackdepth, nlocalsplus; - if (_PyCfg_OptimizedCfgToInstructionSequence(g, umd, code_flags, + if (_PyCfg_OptimizedCfgToInstructionSequence(g, umd, &stackdepth, &nlocalsplus, &optimized_instrs) < 0) { goto error; diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h index 36464764e4d5ad..4bbac998628963 100644 --- a/Python/executor_cases.c.h +++ b/Python/executor_cases.c.h @@ -10850,7 +10850,6 @@ stack_pointer = _PyFrame_GetStackPointer(frame); stack_pointer += -1; #endif - PyTypeObject *tp = PyStackRef_TYPE(iterable); if (tp == &PyTuple_Type || tp == &PyList_Type) { iter = iterable; @@ -16198,7 +16197,7 @@ SET_CURRENT_CACHED_VALUES(0); JUMP_TO_ERROR(); } - assert(STACK_LEVEL() == 0); + assert(STACK_LEVEL() <= 2); _PyFrame_SetStackPointer(frame, stack_pointer); _PyInterpreterFrame *gen_frame = &gen->gi_iframe; frame->instr_ptr++; diff --git a/Python/flowgraph.c b/Python/flowgraph.c index a43f8b45b8775f..04234a6025468e 100644 --- a/Python/flowgraph.c +++ b/Python/flowgraph.c @@ -850,7 +850,7 @@ calculate_stackdepth(cfg_builder *g) int new_depth = depth + effects.net; if (new_depth < 0) { PyErr_Format(PyExc_ValueError, - "Invalid CFG, stack underflow"); + "Invalid CFG, stack underflow at line %d", instr->i_loc.lineno); goto error; } maxdepth = Py_MAX(maxdepth, depth); @@ -971,6 +971,9 @@ label_exception_targets(basicblock *entryblock) { last_yield_except_depth = -1; } } + else if (instr->i_opcode == RETURN_GENERATOR) { + instr->i_except = NULL; + } else { instr->i_except = handler; } @@ -3718,36 +3721,10 @@ build_cellfixedoffsets(_PyCompile_CodeUnitMetadata *umd) static int insert_prefix_instructions(_PyCompile_CodeUnitMetadata *umd, basicblock *entryblock, - int *fixed, int nfreevars, int code_flags) + int *fixed, int nfreevars) { assert(umd->u_firstlineno > 0); - /* Add the generator prefix instructions. */ - if (IS_GENERATOR(code_flags)) { - /* Note that RETURN_GENERATOR + POP_TOP have a net stack effect - * of 0. This is because RETURN_GENERATOR pushes an element - * with _PyFrame_StackPush before switching stacks. - */ - - location loc = LOCATION(umd->u_firstlineno, umd->u_firstlineno, -1, -1); - cfg_instr make_gen = { - .i_opcode = RETURN_GENERATOR, - .i_oparg = 0, - .i_loc = loc, - .i_target = NULL, - .i_except = NULL, - }; - RETURN_IF_ERROR(basicblock_insert_instruction(entryblock, 0, &make_gen)); - cfg_instr pop_top = { - .i_opcode = POP_TOP, - .i_oparg = 0, - .i_loc = loc, - .i_target = NULL, - .i_except = NULL, - }; - RETURN_IF_ERROR(basicblock_insert_instruction(entryblock, 1, &pop_top)); - } - /* Set up cells for any variable that escapes, to be put in a closure. */ const int ncellvars = (int)PyDict_GET_SIZE(umd->u_cellvars); if (ncellvars) { @@ -3845,7 +3822,7 @@ fix_cell_offsets(_PyCompile_CodeUnitMetadata *umd, basicblock *entryblock, int * } static int -prepare_localsplus(_PyCompile_CodeUnitMetadata *umd, cfg_builder *g, int code_flags) +prepare_localsplus(_PyCompile_CodeUnitMetadata *umd, cfg_builder *g) { assert(PyDict_GET_SIZE(umd->u_varnames) < INT_MAX); assert(PyDict_GET_SIZE(umd->u_cellvars) < INT_MAX); @@ -3862,7 +3839,7 @@ prepare_localsplus(_PyCompile_CodeUnitMetadata *umd, cfg_builder *g, int code_fl } // This must be called before fix_cell_offsets(). - if (insert_prefix_instructions(umd, g->g_entryblock, cellfixedoffsets, nfreevars, code_flags)) { + if (insert_prefix_instructions(umd, g->g_entryblock, cellfixedoffsets, nfreevars)) { PyMem_Free(cellfixedoffsets); return ERROR; } @@ -3983,7 +3960,7 @@ _PyCfg_ToInstructionSequence(cfg_builder *g, _PyInstructionSequence *seq) int _PyCfg_OptimizedCfgToInstructionSequence(cfg_builder *g, - _PyCompile_CodeUnitMetadata *umd, int code_flags, + _PyCompile_CodeUnitMetadata *umd, int *stackdepth, int *nlocalsplus, _PyInstructionSequence *seq) { @@ -3994,16 +3971,7 @@ _PyCfg_OptimizedCfgToInstructionSequence(cfg_builder *g, return ERROR; } - /* prepare_localsplus adds instructions for generators that push - * and pop an item on the stack. This assertion makes sure there - * is space on the stack for that. - * It should always be true, because a generator must have at - * least one expression or call to INTRINSIC_STOPITERATION_ERROR, - * which requires stackspace. - */ - assert(!(IS_GENERATOR(code_flags) && *stackdepth == 0)); - - *nlocalsplus = prepare_localsplus(umd, g, code_flags); + *nlocalsplus = prepare_localsplus(umd, g); if (*nlocalsplus < 0) { return ERROR; } diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h index 42058066cbd12d..353081cd53ef46 100644 --- a/Python/generated_cases.c.h +++ b/Python/generated_cases.c.h @@ -6188,7 +6188,6 @@ _Py_GatherStats_GetIter(iterable); stack_pointer = _PyFrame_GetStackPointer(frame); #endif - PyTypeObject *tp = PyStackRef_TYPE(iterable); if (tp == &PyTuple_Type || tp == &PyList_Type) { iter = iterable; @@ -10386,7 +10385,7 @@ if (gen == NULL) { JUMP_TO_LABEL(error); } - assert(STACK_LEVEL() == 0); + assert(STACK_LEVEL() <= 2); _PyFrame_SetStackPointer(frame, stack_pointer); _PyInterpreterFrame *gen_frame = &gen->gi_iframe; frame->instr_ptr++; diff --git a/Python/instruction_sequence.c b/Python/instruction_sequence.c index e2db46b48930d6..42cb148ac97c01 100644 --- a/Python/instruction_sequence.c +++ b/Python/instruction_sequence.c @@ -154,6 +154,13 @@ _PyInstructionSequence_InsertInstruction(instr_sequence *seq, int pos, return SUCCESS; } +_PyInstruction +_PyInstructionSequence_GetInstruction(instr_sequence *seq, int pos) +{ + assert(pos >= 0 && pos < seq->s_used); + return seq->s_instrs[pos]; +} + int _PyInstructionSequence_SetAnnotationsCode(instr_sequence *seq, instr_sequence *annotations) From 0d9ded357e87bad1832acf768fae272be1fc3897 Mon Sep 17 00:00:00 2001 From: Mark Shannon Date: Thu, 8 Jan 2026 14:55:40 +0000 Subject: [PATCH 2/2] Add news --- .../2026-01-08-14-55-31.gh-issue-143569.-Ltu3c.rst | 3 +++ 1 file changed, 3 insertions(+) create mode 100644 Misc/NEWS.d/next/Core_and_Builtins/2026-01-08-14-55-31.gh-issue-143569.-Ltu3c.rst diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-01-08-14-55-31.gh-issue-143569.-Ltu3c.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-01-08-14-55-31.gh-issue-143569.-Ltu3c.rst new file mode 100644 index 00000000000000..c625c3b9a84d20 --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-01-08-14-55-31.gh-issue-143569.-Ltu3c.rst @@ -0,0 +1,3 @@ +Generator expressions in 3.15 now conform to the documented behavior when +the iterable does not support iteration. This matches the behavior in 3.14 +and earlier