too mild for the standard condition classes, typically hints about how
efficiency might be improved. The @code{sb-ext:code-deletion-note}, a
subtype of @code{compiler-note}, is signalled when the compiler
-deletes user-supplied code, usually after proving that the code in
-question is unreachable.
+deletes user-supplied code after proving that the code in question is
+unreachable.
Future work for SBCL includes expanding this hierarchy of types to
allow more fine-grained control over emission of diagnostic messages.
Used when @code{(or (>= safety 2) (>= safety speed 1))}.
@item Weak Type Checks
-Declared types may be simplified into faster to check supertypes: for example,
-@code{(and unsigned-byte fixnum)} is simplified into @code{fixnum}.
+Declared types may be simplified into faster to check supertypes: for
+example, @code{(or (integer -17 -7) (integer 7 17))} is simplified
+into @code{(integer -17 17)}.
@strong{Note}: it is relatively easy to corrupt the heap when weak
type checks are used if the program contains type-errors.