diff --git a/src/cc65/assignment.c b/src/cc65/assignment.c
index e51dde9ab..a66c495da 100644
--- a/src/cc65/assignment.c
+++ b/src/cc65/assignment.c
@@ -104,10 +104,16 @@ static void CopyStruct (ExprDesc* LExpr, ExprDesc* RExpr)
 
     } else {
 
-        /* The rhs cannot happen to be loaded in the primary as it is too big */
+        /* Load the address of rhs into the primary */
         if (!ED_IsLocExpr (RExpr)) {
             ED_AddrExpr (RExpr);
             LoadExpr (CF_NONE, RExpr);
+        } else if (RExpr->IVal != 0) {
+            /* We have an expression in the primary plus a constant
+            ** offset. Adjust the value in the primary accordingly.
+            */
+            g_inc (CF_PTR | CF_CONST, RExpr->IVal);
+            RExpr->IVal = 0;
         }
 
         /* Push the address of the rhs as the source of memcpy */
diff --git a/test/todo/bug2566.c b/test/val/bug2566.c
similarity index 100%
rename from test/todo/bug2566.c
rename to test/val/bug2566.c