Refactor future feature handling

Replace individual slots in PyFutureFeatures with a single bitmask
with one field per feature.  The flags for this bitmask are the same
as the flags used in the co_flags slot of a code object.

    XXX This means we waste several bits, because they are used
    for co_flags but have no meaning for future statements.  Don't
    think this is an issue.

Remove the NESTED_SCOPES_DEFAULT define and others.  Not sure what
they were for anyway.

Remove all the PyCF_xxx flags, but define PyCF_MASK in terms of the
CO_xxx flags that are relevant for this release.

Change definition of PyCompilerFlags so that cf_flags matches
co_flags.

1 files changed, 2 insertions, 7 deletions

diff --git a/Include/pythonrun.h b/Include/pythonrun.h
index 55e1ddd..95ac15c 100644
--- a/Include/pythonrun.h
+++ b/Include/pythonrun.h
@@ -7,14 +7,9 @@
 extern "C" {
 #endif
 
-/* These flags are named after the __future__ statements that introduced
-   them.  May not remain true for later additions, so fiddle this comment
-   accordingly then. */
-#define PyCF_NESTED_SCOPES	(0x00000001UL)
-#define PyCF_GENERATORS		(0x00000002UL)
-#define PyCF_DIVISION		(0x00000004UL)
+#define PyCF_MASK (CO_GENERATOR_ALLOWED | CO_FUTURE_DIVISION)
 typedef struct {
-	unsigned long cf_flags;  /* bitmask of PyCF_xxx flags */
+	int cf_flags;  /* bitmask of CO_xxx flags relevant to future */
 } PyCompilerFlags;
 
 DL_IMPORT(void) Py_SetProgramName(char *);