Created attachment 215807 [details]
Color wheel test case
The attached test case where we draw a color wheel programmatically using the CanvasRenderingContext2D API renders incorrectly on ToT where it used to work fine. Regressing shows that this rendered as expected as of r155565 and incorrectly with r155567, r155567 was untested but given it's a Windows-specific fix, it's likely that this regressed in http://trac.webkit.org/changeset/155567, a code change introduced to fix https://bugs.webkit.org/show_bug.cgi?id=121141.
Looks like a fun bug!
Yeah, it's obviously a miscompile in hsl2rgb().
Created attachment 215883 [details]
Landed in http://trac.webkit.org/changeset/158556