Created attachment 14400 [details]
Source for test case
Setting an image pattern as the source and then stroking the line does not seem to work with the SVG backend.
The attached test case takes a PNG file (also attached) and draws a horizontal line with it. The SVG file that is produced looks like it is trying to do something, but neither inkscape, rsvg nor firefox seems to render anything.
Compiling the test case with -DPDF to produce PDF output gives a PDF file that does seem to draw the line as expected.
Created attachment 14401 [details]
Image for pattern
Could you please attach the resulting SVG file ?
Created attachment 14461 [details]
Example of failing output
Here's an example of the SVG produced by the test case, as requested.
Fixed in cairo HEAD.