Bug 430810 – [PATCH] Backport patch to avoid -fno-strict-aliasing from Python 3.x to Python 2.7.3

• Status: RESOLVED CANTFIX
• Product: Gentoo Linux

[Description Richard Yao (RETIRED) 2012-08-10 17:13:58 UTC]

Created attachment 320912 [details, diff]
Backported patch

Currently, Python 2.7.3 is being built with -fno-strict-aliasing. Python 3.x has been patched at upstream to avoid -fno-strict-aliasing and the back can be trivially backported to Python 2.7.3.

I have attached the backported patch. It provides performance benefits to anyone using GCC 4.3 or later.

[Comment 1 Mike Gilbert 2012-08-10 17:42:49 UTC]

Looks ok to me.

Do we want to add this to the patchset, or just stick it in FILESDIR?

[Comment 2 Richard Yao (RETIRED) 2012-08-10 18:16:06 UTC]

(In reply to comment #1)
> Looks ok to me.
> 
> Do we want to add this to the patchset, or just stick it in FILESDIR?

It looks like all of the python 2.7.3 patches are in the patch set. It probably would be best to add it there.

[Comment 3 Rafał Mużyło 2012-08-11 06:17:01 UTC]

IIRC, those warnings are *not* false positives in <3.0 - there's a common macro in 2.x, that does violate strict aliasing and *does* produce wrong code then.

You'd better ask Arfrever to be sure.

[Comment 4 Arfrever Frehtes Taifersar Arahesis 2012-08-11 14:10:52 UTC]

This patch is unacceptable.
A part of API of Python 2 is incompatible with strict-aliasing rules.
http://www.python.org/dev/peps/pep-3123/

[Comment 5 David J Cozatt 2012-08-11 14:51:46 UTC]

This bug should then be closed