diff --git a/compiler/prelude/primops.txt.pp b/compiler/prelude/primops.txt.pp
index adb2e110ff8ced4fc4348f767daa93185a37c4bf..471cba1b9fd552b635f7813e0377f77215293d8f 100644
--- a/compiler/prelude/primops.txt.pp
+++ b/compiler/prelude/primops.txt.pp
@@ -1801,6 +1801,7 @@ pseudoop   "unsafeCoerce#"
          * Casting {\tt Any} back to the real type
 
          * Casting an unboxed type to another unboxed type of the same size
+           (but not coercions between floating-point and integral types)
 
          * Casting between two types that have the same runtime representation.  One case is when
            the two types differ only in "phantom" type parameters, for example