Coverity PW.PARAMETER_HIDDEN - CID 10457

This bug is exported from the Coverity Integration Manager on Canonical's servers. For information on how this is done please see this website: https://wiki.ubuntu.com/CanonicalProductStrategy/Coverity
CID: 10457
Checker: PW.PARAMETER_HIDDEN
Category: No category available
CWE definition: No definition available
File: /tmp/buildd/overlay-scrollbar-0.2.14/os/os-scrollbar.c
Function: No function name available
Code snippet:
813 {
814 cairo_region_t *monitor_workarea;
815 cairo_region_t *struts_region;
816 cairo_rectangle_int_t tmp_rect;
CID 10457 - PW.PARAMETER_HIDDEN
declaration hides parameter "y" (declared at line 780)
817 gint i, y, height;
818
819 y = rect.y;
820 height = rect.y + rect.height;
821
822 /* Full monitor region. */