the old CO_FUTURE flags can't be commented out

Include/code.h

@@ -42,7 +42,6 @@ typedef struct {
 */
 #define CO_NOFREE       0x0040
 
-#if 0
 /* These are no longer used. */
 #define CO_GENERATOR_ALLOWED    0x1000
 #define CO_FUTURE_DIVISION    	0x2000
@@ -50,7 +49,6 @@ typedef struct {
 #define CO_FUTURE_WITH_STATEMENT  0x8000
 #define CO_FUTURE_PRINT_FUNCTION  0x10000
 #define CO_FUTURE_UNICODE_LITERALS 0x20000
-#endif
 
 #define CO_FUTURE_BARRY_AS_BDFL  0x40000
 

Include/pythonrun.h

@@ -7,7 +7,9 @@
 extern "C" {
 #endif
 
-#define PyCF_MASK CO_FUTURE_BARRY_AS_BDFL
+#define PyCF_MASK (CO_FUTURE_DIVISION | CO_FUTURE_ABSOLUTE_IMPORT | \
+                   CO_FUTURE_WITH_STATEMENT | CO_FUTURE_PRINT_FUNCTION | \
+                   CO_FUTURE_UNICODE_LITERALS | CO_FUTURE_BARRY_AS_BDFL)
 #define PyCF_MASK_OBSOLETE 0
 #define PyCF_SOURCE_IS_UTF8  0x0100
 #define PyCF_DONT_IMPLY_DEDENT 0x0200

Misc/NEWS

@@ -24,6 +24,11 @@ Core and Builtins
 
 - Issue #4856: Remove checks for win NT.
 
+C-API
+-----
+
+- The code flags for old __future__ features are now available again.
+
 Library
 -------