Bug 83314 - Wrong XcmsTekHVCFormat to XcmsRGBFromat color conversion on 32 bit systems
Summary: Wrong XcmsTekHVCFormat to XcmsRGBFromat color conversion on 32 bit systems
Status: RESOLVED MOVED
Alias: None
Product: xorg
Classification: Unclassified
Component: Lib/Xlib (show other bugs)
Version: unspecified
Hardware: x86 (IA32) All
: medium normal
Assignee: Xorg Project Team
QA Contact: Xorg Project Team
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-08-31 20:48 UTC by Dimitri Sokolyuk
Modified: 2018-08-10 20:10 UTC (History)
0 users

See Also:
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Attachments
Test application and results for 32 and 64 bit systems (4.05 KB, text/plain)
2014-08-31 20:48 UTC, Dimitri Sokolyuk 		no flags Details
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Description Dimitri Sokolyuk 2014-08-31 20:48:09 UTC 
Created attachment 105512 [details]
Test application and results for 32 and 64 bit systems

Conversion from XcmsTekHVCFormat into XcmsRGBFromat gives on 32 bit systems wrong results for upper half of Hue values (over ca. 148.0). Results in lover half are tinted too. 64 bit systems are not affected.

Simple test application is included along with results for 32 bit system (wrong results) and for 64 bit system (expected results).

Tested on 32/64bit OpenBSD 5.5/5.6, OS X 10.9 (XQuartz) and various 32/64bit Linux systems. Bug appears at least (but is not limited to) on Xorg versions 1.14.5 to 1.15.2.

See also discussion on bug hunting: https://www.linux.org.ru/forum/development/10810167 (russian)
Comment 1 Dimitri Sokolyuk 2014-08-31 21:59:21 UTC 
UPD: as far as I could go back in time, the bug exists on additionally tested Xorg 1.8.2 (OpenBSD/i386 4.8) and Xorg 7.2.0 (OpenBSD/i386 4.2) too. And may be ever prior.
Comment 2 Dimitri Sokolyuk 2014-09-01 10:52:18 UTC 
may be related: https://bugs.freedesktop.org/show_bug.cgi?id=9949
Comment 3 GitLab Migration User 2018-08-10 20:10:49 UTC 
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/xorg/lib/libx11/issues/37.

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