diff --git a/src/mesa/main/attrib.c b/src/mesa/main/attrib.c
index e5672a9ee5a..98c4b8afdc7 100644
--- a/src/mesa/main/attrib.c
+++ b/src/mesa/main/attrib.c
@@ -1359,8 +1359,7 @@ copy_array_object(struct gl_context *ctx,
    dest->NonZeroDivisorMask = src->NonZeroDivisorMask;
    dest->_AttributeMapMode = src->_AttributeMapMode;
    dest->NewArrays = src->NewArrays;
-   dest->NumUpdates = src->NumUpdates;
-   dest->IsDynamic = src->IsDynamic;
+   /* skip NumUpdates and IsDynamic because they can only increase, not decrease */
 }
 
 /**