--- a/QuadFloat.st	Mon Jun 10 23:54:36 2019 +0200
+++ b/QuadFloat.st	Mon Jun 10 23:58:26 2019 +0200
@@ -2164,7 +2164,7 @@
     uiA64 = uA.ui.v64;
     uiA0  = uA.ui.v0;
     if (isNaNF128UI( uiA64, uiA0 )) return a;
-    uiA64 ^= 0x80000000;
+    uA.ui.v64 ^= 0x80000000;
     return uA.f;
 }