[pypy-commit] pypy release-2.1.x: Change the magic number in .pyc files: we used default_magic = 0xf303+2,

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: release-2.1.x
Changeset: r65825:43efd6376dab
Date: 2013-07-30 20:42 +0200
http://bitbucket.org/pypy/pypy/changeset/43efd6376dab/

Log:	Change the magic number in .pyc files: we used default_magic =
	0xf303+2, now it is 0xf303+6. The most recent incompatible change
	that requires this change is e953dfbc7f0a.

diff --git a/pypy/interpreter/pycode.py b/pypy/interpreter/pycode.py
--- a/pypy/interpreter/pycode.py
+++ b/pypy/interpreter/pycode.py
@@ -31,7 +31,7 @@
 # Magic numbers for the bytecode version in code objects.
 # See comments in pypy/module/imp/importing.
 cpython_magic, = struct.unpack("<i", imp.get_magic())   # host magic number
-default_magic = (168686339+2) | 0x0a0d0000              # this PyPy's magic
+default_magic = (0xf303 + 6) | 0x0a0d0000               # this PyPy's magic
                                                         # (from CPython 2.7.0)
 
 # cpython_code_signature helper
diff --git a/pypy/module/imp/importing.py b/pypy/module/imp/importing.py
--- a/pypy/module/imp/importing.py
+++ b/pypy/module/imp/importing.py
@@ -833,21 +833,16 @@
 """
 
 # picking a magic number is a mess.  So far it works because we
-# have only one extra opcode, which bumps the magic number by +2, and CPython
-# leaves a gap of 10 when it increases
-# its own magic number.  To avoid assigning exactly the same numbers
-# as CPython we always add a +2.  We'll have to think again when we
-# get three more new opcodes
+# have only one extra opcode which might or might not be present.
+# CPython leaves a gap of 10 when it increases its own magic number.
+# To avoid assigning exactly the same numbers as CPython, we can pick
+# any number between CPython + 2 and CPython + 9.  Right now,
+# default_magic = CPython + 6.
 #
-#  * CALL_METHOD            +2
-#
-# In other words:
-#
-#     default_magic        -- used by CPython without the -U option
-#     default_magic + 1    -- used by CPython with the -U option
-#     default_magic + 2    -- used by PyPy without any extra opcode
-#     ...
-#     default_magic + 5    -- used by PyPy with both extra opcodes
+#     default_magic - 6    -- used by CPython without the -U option
+#     default_magic - 5    -- used by CPython with the -U option
+#     default_magic        -- used by PyPy without the CALL_METHOD opcode
+#     default_magic + 2    -- used by PyPy with the CALL_METHOD opcode
 #
 from pypy.interpreter.pycode import default_magic
 MARSHAL_VERSION_FOR_PYC = 2