Function rustc_codegen_ssa::base::cast_to_dyn_star

pub fn cast_to_dyn_star<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
    bx: &mut Bx,
    src: Bx::Value,
    src_ty_and_layout: TyAndLayout<'tcx>,
    dst_ty: Ty<'tcx>,
    old_info: Option<Bx::Value>
) -> (Bx::Value, Bx::Value)

Coerces src to dst_ty which is guaranteed to be a dyn* type.