diff --git a/src/compiler/nir/nir_lower_mediump.c b/src/compiler/nir/nir_lower_mediump.c
index 2e7a40d2359..3da34eaa0d1 100644
--- a/src/compiler/nir/nir_lower_mediump.c
+++ b/src/compiler/nir/nir_lower_mediump.c
@@ -515,7 +515,7 @@ nir_lower_mediump_vars_impl(nir_function_impl *impl, nir_variable_mode modes,
 
             case nir_intrinsic_copy_deref: {
                nir_deref_instr *dst = nir_src_as_deref(intrin->src[0]);
-               nir_deref_instr *src = nir_src_as_deref(intrin->src[0]);
+               nir_deref_instr *src = nir_src_as_deref(intrin->src[1]);
                /* If we convert once side of a copy and not the other, that
                 * would be very bad.
                 */