[3.8] bpo-39562: Prevent collision of future and compiler flags (GH-19230) (GH-19835)
The constant values of future flags in the __future__ module
is updated in order to prevent collision with compiler flags.
Previously PyCF_ALLOW_TOP_LEVEL_AWAIT was clashing
with CO_FUTURE_DIVISION..
(cherry picked from commit 4454057269b995341b04d13f0bf97f96080f27d0)
Co-authored-by: Batuhan Taşkaya <batuhanosmantaskaya@gmail.com>
diff --git a/Include/code.h b/Include/code.h
index 3afddd2..a1cd58f 100644
--- a/Include/code.h
+++ b/Include/code.h
@@ -88,19 +88,19 @@
#define CO_ITERABLE_COROUTINE 0x0100
#define CO_ASYNC_GENERATOR 0x0200
-/* These are no longer used. */
-#if 0
-#define CO_GENERATOR_ALLOWED 0x1000
-#endif
-#define CO_FUTURE_DIVISION 0x2000
-#define CO_FUTURE_ABSOLUTE_IMPORT 0x4000 /* do absolute imports by default */
-#define CO_FUTURE_WITH_STATEMENT 0x8000
-#define CO_FUTURE_PRINT_FUNCTION 0x10000
-#define CO_FUTURE_UNICODE_LITERALS 0x20000
+/* bpo-39562: These constant values are changed in Python 3.9
+ to prevent collision with compiler flags. CO_FUTURE_ and PyCF_
+ constants must be kept unique. PyCF_ constants can use bits from
+ 0x0100 to 0x10000. CO_FUTURE_ constants use bits starting at 0x20000. */
+#define CO_FUTURE_DIVISION 0x20000
+#define CO_FUTURE_ABSOLUTE_IMPORT 0x40000 /* do absolute imports by default */
+#define CO_FUTURE_WITH_STATEMENT 0x80000
+#define CO_FUTURE_PRINT_FUNCTION 0x100000
+#define CO_FUTURE_UNICODE_LITERALS 0x200000
-#define CO_FUTURE_BARRY_AS_BDFL 0x40000
-#define CO_FUTURE_GENERATOR_STOP 0x80000
-#define CO_FUTURE_ANNOTATIONS 0x100000
+#define CO_FUTURE_BARRY_AS_BDFL 0x400000
+#define CO_FUTURE_GENERATOR_STOP 0x800000
+#define CO_FUTURE_ANNOTATIONS 0x1000000
/* This value is found in the co_cell2arg array when the associated cell
variable does not correspond to an argument. */
diff --git a/Include/compile.h b/Include/compile.h
index 1cda955..015584d 100644
--- a/Include/compile.h
+++ b/Include/compile.h
@@ -18,12 +18,18 @@
CO_FUTURE_UNICODE_LITERALS | CO_FUTURE_BARRY_AS_BDFL | \
CO_FUTURE_GENERATOR_STOP | CO_FUTURE_ANNOTATIONS)
#define PyCF_MASK_OBSOLETE (CO_NESTED)
+
+/* bpo-39562: CO_FUTURE_ and PyCF_ constants must be kept unique.
+ PyCF_ constants can use bits from 0x0100 to 0x10000.
+ CO_FUTURE_ constants use bits starting at 0x20000. */
#define PyCF_SOURCE_IS_UTF8 0x0100
#define PyCF_DONT_IMPLY_DEDENT 0x0200
#define PyCF_ONLY_AST 0x0400
#define PyCF_IGNORE_COOKIE 0x0800
#define PyCF_TYPE_COMMENTS 0x1000
#define PyCF_ALLOW_TOP_LEVEL_AWAIT 0x2000
+#define PyCF_COMPILE_MASK (PyCF_ONLY_AST | PyCF_ALLOW_TOP_LEVEL_AWAIT | \
+ PyCF_TYPE_COMMENTS | PyCF_DONT_IMPLY_DEDENT)
#ifndef Py_LIMITED_API
typedef struct {