[cairo] Performance regression on Windows

[Nicolas Dufour]

Hello,
I'm currently updating some libraries for Inkscape on win32, and notice a serious UI slowdown when updating the Cairo libs. Everything works as expected with Cairo-1.11.2 (the dll we provide with the latest stable Inkscape version, 0.48.4), but the Inkscape UI becomes very slow when drawing or moving objects on canvas with a more recent Cairo version (tested with 1.12.8, 1.12.14, 1.12.16 and yesterdays git version). I've also updated Pixman to 0.32.2, but noticed no regression with the Pixman update as long as I don't update Cairo too. The compiler used to build Cairo and Pixman is TDM-GCC-4.6.1 (required to be consistent with the other libs in the Inkscape win32 repo.).

Other operating systems are not affected (tested on Debian stable with Cairo-1.12.2 and Pixman-0.26, but other Inkscape users confirmed it's ok with recent Ubuntu and OS-X versions).

Could you tell me if the performance issue we experience is a known bug?

Related question: I wanted to investigate with cairo-trace, but it doesn't output any trace file. Is cairo-trace expected to work on Windows too?

Regards,
--
Nicolas