I don't often shoot into the sun, but I have a recent example of when I did. I was following the movement of waders in front of the incoming tide in The Wash, Norfolk, UK. A murky afternoon sun on 29th September. I could have avoided the sun by a long walk left or right, but I did not. I rather like the result though it is not adequate for the Knot and other birds. Flare does not seem to be a problem in this picture, well not to my eyes. I post a crop from the centre as well as the whole frame minus the edghe crop to allow for my not-so-level hand holding of the camera. Perhaps the haze saved the day.
D800E, Zeiss 100 mm f2 makro, @ f8, ISO 140, 1/400 sec, ev + -0.67. Adobe ACR, Photoshop PS6, no special manipulation.