[cairo-arc] Protect against division-by-zero.

Avoid a division-by-zero which can only happen if the start angle is
exactly equal to the end angle.

Fixes test/degenerate-arc.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/cairo-arc.c b/src/cairo-arc.c
index 523297062..eed75e715 100644
--- a/src/cairo-arc.c
+++ b/src/cairo-arc.c
@@ -208,7 +208,7 @@ _cairo_arc_in_direction (cairo_t	  *cr,
 				     angle_min, angle_mid,
 				     dir);
 	}
-    } else {
+    } else if (angle_max != angle_min) {
 	cairo_matrix_t ctm;
 	int i, segments;
 	double angle, angle_step;