Bug 264686

Summary:	<dev-libs/glib-2.19 headers cause strict-aliasing errors in dependencies with sys-devel/gcc-4.4
Product:	Gentoo Linux	Reporter:	Daniel J. <sleeperseven>
Component:	[OLD] GCC Porting	Assignee:	Gentoo Linux Gnome Desktop Team <gnome>
Status:	RESOLVED FIXED
Severity:	minor	CC:	esigra
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	http://sunsite.mff.cuni.cz/rawhide20090126-gcc44/glib.aliasing/
Whiteboard:
Package list:		Runtime testing required:	---
Bug Depends on:
Bug Blocks:	249226
Attachments:	Backport of upstream SVN rev 7875

Description Daniel J. 2009-04-02 20:01:04 UTC

When attempting to build a number of apps (listed in the URL above), GCC 4.4 fails due to strict-aliasing errors. A patch against GLib SVN trunk was created by Jakub Jelinek and committed upstream with revision 7875.  I am attaching a backport of the patch against sys-devel/glib-2.18.4.

Comment 1 Daniel J. 2009-04-02 20:01:34 UTC

Created attachment 187133 [details, diff]
Backport of upstream SVN rev 7875

Comment 2 Daniel J. 2009-04-02 20:12:13 UTC

The first upstream glib release containing this fix is 2.19.8.

Comment 3 Gilles Dartiguelongue (RETIRED) gentoo-dev

2009-04-02 20:25:48 UTC

so you're saying strict-aliasing warnings are now errors in gcc-4.4 ?

Comment 4 Daniel J. 2009-04-02 20:57:58 UTC

From what I can tell, -fstrict-aliasing is enabled by default in GCC 4.4.

Comment 5 Gilles Dartiguelongue (RETIRED) gentoo-dev

2009-04-02 21:04:20 UTC

please don't touch the priority fields, gcc 4.4 support isn't top priority for us for now unless somebody from the team dedicates to this.

Comment 6 Ryan Hill (RETIRED) gentoo-dev

2009-04-15 01:04:19 UTC

strict-aliasing has always been enabled at -O2, it's just that every release the gcc devs make more and more optimizations that assume strict-aliasing rules aren't violated.  in 4.4, a strict-aliasing warning is a good sign that something's broken.

(added to gcc-porting overlay)

Comment 7 Gilles Dartiguelongue (RETIRED) gentoo-dev

2009-05-04 22:15:43 UTC

2.20.1 is now in tree but I also added 2.18.4-r2. Thanks for reporting and providing a patch.