diff --git a/libpixelflinger/fixed.cpp b/libpixelflinger/fixed.cpp
index 5b92062..5094537 100644
--- a/libpixelflinger/fixed.cpp
+++ b/libpixelflinger/fixed.cpp
@@ -62,7 +62,8 @@
     int shift;
     x = gglRecipQNormalized(x, &shift);
     shift += 16-q;
-    x += 1L << (shift-1);   // rounding
+    if (shift > 0)
+        x += 1L << (shift-1);   // rounding
     x >>= shift;
     return x;
 }