[issue9530] integer undefined behaviors

Mark Dickinson added the comment: It looks as though all the issues found by John's tool have now been fixed, with the exception of the ctypes issue. There's a separate issue open for that, so I'm closing this issue as fixed. -- resolution: -> fixed status: open -> closed __

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Thanks, Amaury. I see a whole bunch of related issues, but none of them quite seems to capture this exact issue. So I've opened a new bug report: see issue 15119. -- ___ Python tracker

[issue9530] integer undefined behaviors

Amaury Forgeot d'Arc added the comment: Issue3547 looks similar. -- nosy: +amaury.forgeotdarc ___ Python tracker ___ ___ Python-bugs-l

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Meador: I see that you've been working on some ctypes issues; does the ctypes bitfield problem above fall under any of the existing issues, or should I open a new one? -- nosy: +meador.inge ___ Python tracker

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Thanks. It looks like that <<= report has uncovered a bug in the way that ctypes lays out bitfields: in the following, BITS.M should (I believe) look like: . Instead, ctypes is trying to store a bitfield starting at bit position 17 of a short, which doesn'

[issue9530] integer undefined behaviors

John Regehr added the comment: I the tests for today's cpython using IOC and got only the issues below. The on-purpose divide by zero should be OK but the shift by -2 probably wants to be fixed. ARITHMETIC UNDEFINED at : Op: <<=, Reason : Signed Left Shift: Right operand is negative or is g

[issue9530] integer undefined behaviors

Roundup Robot added the comment: New changeset c9c2031cf16d by Mark Dickinson in branch 'default': Add John Regehr to Misc/ACKS for his help with finding integer overflows (issue #9530). http://hg.python.org/cpython/rev/c9c2031cf16d -- ___ Python tr

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: > Alternatively, I can re-run the Python test suite on a Python compiled > using our tool. Let me know if this would be helpful. Definitely helpful if you have the time! Yes, please. Though I do intend to try out the tool for myself at some point.

[issue9530] integer undefined behaviors

Changes by Chris Rebert : -- nosy: +cvrebert ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.

[issue9530] integer undefined behaviors

Changes by Stefan Krah : -- nosy: +skrah ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/

[issue9530] integer undefined behaviors

John Regehr added the comment: Hi folks, I realize it was a long time ago that I reported this issue! Since then our tool has been made available: http://embed.cs.utah.edu/ioc/ In particular, that web page contains a pre-compiled version of the tool for recent Ubuntu on x86-64, that shou

[issue9530] integer undefined behaviors

Changes by Mark Dickinson : -- dependencies: +Integer overflow in classic string formatting ___ Python tracker ___ ___ Python-bugs-list

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: See also issue #13496. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: htt

[issue9530] integer undefined behaviors

Roundup Robot added the comment: New changeset 7e37598a25a6 by Mark Dickinson in branch 'default': Issue #9530: Fix undefined behaviour due to signed overflow in Python/formatter_unicode.c. http://hg.python.org/cpython/rev/7e37598a25a6 -- ___ Python

[issue9530] integer undefined behaviors

John Regehr added the comment: Hi Mark, yes you can run the overflow checker but "easy instructions" depends on whether you feel like building your own LLVM. It is not at all difficult, but it's certainly not as easy as "apt-get install ...". Patch and instructions are here: http://embed.

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: > I'd be happy to re-run the tests sometime. Yes, please! Alternatively, if there are easy instructions for us to re-run these tests, that would be valuable, too. Do I understand correctly that you have a publicly available extension to LLVM for this? > Ba

[issue9530] integer undefined behaviors

Changes by Jesús Cea Avión : -- nosy: +jcea ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.o

[issue9530] integer undefined behaviors

Roundup Robot added the comment: New changeset 71100ef4f7a2 by Mark Dickinson in branch 'default': Issue #9530: Fix undefined behaviour due to signed overflow in testcapi_long.h. http://hg.python.org/cpython/rev/71100ef4f7a2 -- nosy: +python-dev ___

[issue9530] integer undefined behaviors

John Regehr added the comment: This is great. I'd be happy to re-run the tests sometime, and also we're talking with the LLVM folks about getting our patches into the main LLMM tree. Basically it'll act as a more powerful -ftrapv, and the error message will be much better than "aborted". -

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: The issues reported for the datetime, array, itertools and math modules are also already fixed. That just leaves the following two of the reported issues outstanding: : Op: <<=, Reason : Signed Left Shift Error: Right operand is negative or is greater than

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: See also issue #1621. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Status update: all the reported errors from the Objects/ directory have been fixed in the default branch (many of these were fixed recently as part of making sure that the test-suite runs under Clang's -ftrapv option), or are out of date. I haven't checked

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Applied issue9530_1.patch in r83936. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Uns

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Fixed two more bytearray problems in r83768. -- ___ Python tracker ___ ___ Python-bugs-list mailing

[issue9530] integer undefined behaviors

John Regehr added the comment: Hi Mark-- Glad it's useful! We plan to release this tool but haven't done so yet, it still has rough edges. It's LLVM-based and it seems likely they will take our patches. -- ___ Python tracker

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: Here are some fixes for Objects/bytesobject.c and Objects/bytearrayobject.c. More to come. -- keywords: +patch versions: +Python 3.2 -Python 3.3 Added file: http://bugs.python.org/file18415/issue9530_1.patch ___ Py

[issue9530] integer undefined behaviors

Changes by Eric Smith : -- nosy: +eric.smith ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.

[issue9530] integer undefined behaviors

Mark Dickinson added the comment: This is good stuff! Thank you! I'll look through these. Is the tool you used publicly available? -- assignee: -> mark.dickinson nosy: +mark.dickinson ___ Python tracker ___

[issue9530] integer undefined behaviors

New submission from John Regehr : I ran "make test" for today's Python3k snapshot under a tool which detects math operations that the C language considers to have undefined behavior. This was on x86 Linux. The list of undefined behaviors is attached. Hopefully they are self-explanatory, but