x: fix CI build failure

Signed-off-by: Yuxuan Shui <[email protected]>

src/x.c

@@ -394,7 +394,13 @@ uint32_t x_create_region(xcb_connection_t *c, const region_t *reg) {
 	}
 
 	int nrects;
-	auto rects = pixman_region32_rectangles(reg, &nrects);
+#pragma GCC diagnostic push
+// In older pixman versions, pixman_region32_rectangles doesn't take const region_t,
+// instead of dealing with this version difference, just suppress the warning.
+#pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
+#pragma GCC diagnostic ignored "-Wincompatible-pointer-types-discards-qualifiers"
+	const pixman_box32_t *rects = pixman_region32_rectangles(reg, &nrects);
+#pragma GCC diagnostic pop
 	auto xrects = ccalloc(nrects, xcb_rectangle_t);
 	for (int i = 0; i < nrects; i++) {
 		xrects[i] =