diff --git a/SANDBOX.PO b/SANDBOX.PO
index 81f029f..b7d6249 100644
Binary files a/SANDBOX.PO and b/SANDBOX.PO differ
diff --git a/src/toolsrc/sb.pla b/src/toolsrc/sb.pla
index dd8e3d7..d99230c 100644
--- a/src/toolsrc/sb.pla
+++ b/src/toolsrc/sb.pla
@@ -3006,7 +3006,7 @@ def parse_constexpr(valptr, sizeptr)
     word optos
 
     *valptr  = 0
-    *sizeptr = 1
+    ^sizeptr = 1
     matchop  = 0
     optos    = opsp
     repeat