[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-29 Thread STINNER Victor 


STINNER Victor  added the comment:


New changeset 2a852a2b122cf9545909234cdc8fca564dc8f805 by Victor Stinner (Miss 
Islington (bot)) in branch '3.6':
bpo-16086: Fix PyType_GetFlags() documentation (GH-10758) (GH-10790)
https://github.com/python/cpython/commit/2a852a2b122cf9545909234cdc8fca564dc8f805


--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-29 Thread STINNER Victor 


STINNER Victor  added the comment:


New changeset e754159ef0af99a4124dd041ab7ceb77fcc922ad by Victor Stinner (Miss 
Islington (bot)) in branch '3.7':
bpo-16086: Fix PyType_GetFlags() documentation (GH-10758) (GH-10789)
https://github.com/python/cpython/commit/e754159ef0af99a4124dd041ab7ceb77fcc922ad


--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-29 Thread miss-islington 


Change by miss-islington :


--
pull_requests: +10037

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-29 Thread STINNER Victor 


STINNER Victor  added the comment:


New changeset 9fbcfc08e5814d7aa9287740187e461425a99f67 by Victor Stinner (Eddie 
Elizondo) in branch 'master':
bpo-16086: Fix PyType_GetFlags() documentation (GH-10758)
https://github.com/python/cpython/commit/9fbcfc08e5814d7aa9287740187e461425a99f67


--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-29 Thread miss-islington 


Change by miss-islington :


--
pull_requests: +10036

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2018-11-28 Thread Eddie Elizondo 


Change by Eddie Elizondo :


--
pull_requests: +10032

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2013-01-15 Thread Jesús Cea Avión 

Changes by Jesús Cea Avión j...@jcea.es:


--
nosy: +jcea

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-30 Thread Roundup Robot 

Roundup Robot added the comment:

New changeset 10795aac6df7 by Victor Stinner in branch 'default':
Issue #16086: PyTypeObject.tp_flags and PyType_Spec.flags are now unsigned
http://hg.python.org/cpython/rev/10795aac6df7

--
nosy: +python-dev

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-30 Thread STINNER Victor 

Changes by STINNER Victor victor.stin...@gmail.com:


--
resolution:  - fixed
status: open - closed

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-30 Thread Serhiy Storchaka 

Serhiy Storchaka added the comment:

Note that Py_TPFLAGS_INT_SUBCLASS already not used in Python 3.x. One bit of 
tp_flags can be freed.

--
nosy: +serhiy.storchaka

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-30 Thread STINNER Victor 

STINNER Victor added the comment:

 Note that Py_TPFLAGS_INT_SUBCLASS already not used in Python 3.x. One bit of 
 tp_flags can be freed.

Please open a new issue if you consider this issue important enough.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-30 Thread Serhiy Storchaka 

Serhiy Storchaka added the comment:

See also issue9307.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-12 Thread STINNER Victor 

STINNER Victor added the comment:

Can anyone review my new patch, unsigned_tp_flags-2.patch?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-01 Thread Martin v . Löwis 

Martin v. Löwis added the comment:

What matters is that precompiled stay compatible; in addition, existing source 
code should continue to compile unmodified.

In the specific case, the flags type also shows up in PyType_Spec. As a 
consequence, the actual TPFLAGS_ values *do* constitute a part of the API.

OTOH, a number of the flags are not considered part of the API at all 
(unfortunately, they aren't explicitly excluded, either). Before we make such a 
change, we should really declare what flags are meant to be by an extension 
module, and what flags are implementation details only to be used by the object 
runtime itself.

Wrt. the proposed change: changing tp_flags to unsigned int is fine. I cannot 
see any real problem with changing PyType_Spec.flags to unsigned int - changing 
it to unsigned long would be incompatible on some systems.

Wrt. changing the existing flags: I'd prefer some deprecation procedure that 
just bans them from being used in an extension module (ultimately wrapping them 
within Py_BUILD_CORE). Once they are deprecated, changing their type is clearly 
fine.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-01 Thread STINNER Victor 

STINNER Victor added the comment:

tp_flags type is long, not int.
Le 1 oct. 2012 16:42, Martin v. Löwis rep...@bugs.python.org a écrit :


 Martin v. Löwis added the comment:

 What matters is that precompiled stay compatible; in addition, existing
 source code should continue to compile unmodified.

 In the specific case, the flags type also shows up in PyType_Spec. As a
 consequence, the actual TPFLAGS_ values *do* constitute a part of the API.

 OTOH, a number of the flags are not considered part of the API at all
 (unfortunately, they aren't explicitly excluded, either). Before we make
 such a change, we should really declare what flags are meant to be by an
 extension module, and what flags are implementation details only to be used
 by the object runtime itself.

 Wrt. the proposed change: changing tp_flags to unsigned int is fine. I
 cannot see any real problem with changing PyType_Spec.flags to unsigned int
 - changing it to unsigned long would be incompatible on some systems.

 Wrt. changing the existing flags: I'd prefer some deprecation procedure
 that just bans them from being used in an extension module (ultimately
 wrapping them within Py_BUILD_CORE). Once they are deprecated, changing
 their type is clearly fine.

 --

 ___
 Python tracker rep...@bugs.python.org
 http://bugs.python.org/issue16086
 ___


--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-01 Thread Martin v . Löwis 

Martin v. Löwis added the comment:

 tp_flags type is long, not int.

Indeed, and PyType_Spec.flags is int, not long.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-10-01 Thread STINNER Victor 

STINNER Victor added the comment:

 tp_flags type is long, not int.

Oh, I misunderstood what MvL wrote, sorry. I missed PyType_Spec structure.

Here is an updated and more complete patch. I changed the return code of 
PyType_GetFlags(), instead of changing PyType_HasFeature() macro.

 OTOH, a number of the flags are not considered part of the API at all 
 (unfortunately, they aren't explicitly excluded, either). Before we make such 
 a change, we should really declare what flags are meant to be by an extension 
 module, and what flags are implementation details only to be used by the 
 object runtime itself.

Can't we decide that later? (in other issue?)

--
Added file: http://bugs.python.org/file27380/unsigned_tp_flags-2.patch

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-09-30 Thread Antoine Pitrou 

Antoine Pitrou added the comment:

Ok, I'm not Martin, but I'll try to answer. An ABI pertains to the interfaces 
exposed by compiled object code, not source code. With C, function signatures 
in compiled code don't keep any type information (*), and they obviously 
doesn't know about macros either. So I'd answer No to both questions :-)

(*) it would be different with C++, because of name mangling

--
nosy: +pitrou

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-09-29 Thread STINNER Victor 

New submission from STINNER Victor:

1L  31 is undefined if long is 32 bits long. We should use unsigned long 
for PyTypeObject.tp_flags.

Attached patch implements this fix. I don't know if it breaks somehow the 
backward compatibility.

See also issues #1621 and #7406.

--
components: Interpreter Core
files: unsigned_tp_flags.patch
keywords: patch
messages: 171574
nosy: ezio.melotti, haypo, mark.dickinson
priority: normal
severity: normal
status: open
title: tp_flags: Undefined behaviour with 32 bits long
versions: Python 3.4
Added file: http://bugs.python.org/file27347/unsigned_tp_flags.patch

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-09-29 Thread Mark Dickinson 

Mark Dickinson added the comment:

Victor:  you missed one. :-)

#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION (3L15)

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-09-29 Thread Mark Dickinson 

Mark Dickinson added the comment:

Actually, I think it'll be messy to make this work:  PyType_GetFlags is part of 
the stable ABI, so that's got to continue to return a long rather than an 
unsigned long.  And then we've got, in object.h:

#ifdef Py_LIMITED_API
#define PyType_HasFeature(t,f)  ((PyType_GetFlags(t)  (f)) != 0)
#else
#define PyType_HasFeature(t,f)  (((t)-tp_flags  (f)) != 0)
#endif

So we'd need an extra cast from long to unsigned long in the first branch.

I suggest instead just replacing that one occurrence of (1L  31) with 
(long)(1UL  31) to get around the undefined behaviour.


P.S. The docs would also need to be updated in these two files:

   Doc/c-api/typeobj.rst
   Doc/includes/typestruct.h

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue16086] tp_flags: Undefined behaviour with 32 bits long

2012-09-29 Thread Mark Dickinson 

Mark Dickinson added the comment:

Martin, some things I'm not clear on w.r.t. the stable ABI.

(1) Do defined constants like Py_TPFLAGS_INT_SUBCLASS form part of the stable 
ABI?

(2) Would changing the type of Py_TPFLAGS_INT_SUBCLASS from long to unsigned 
long break the stable ABI?

--
nosy: +loewis

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue16086
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com