+(defknown style-warn (t &rest t) null ())
+
+(defknown sc-number-or-lose (symbol) sc-number
+ (foldable))
+
+;;;; memory barriers
+
+(defknown sb!vm:%compiler-barrier () (values) ())
+(defknown sb!vm:%memory-barrier () (values) ())
+(defknown sb!vm:%read-barrier () (values) ())
+(defknown sb!vm:%write-barrier () (values) ())
+(defknown sb!vm:%data-dependency-barrier () (values) ())
+
+
+;;;; atomic ops
+(defknown %compare-and-swap-svref (simple-vector index t t) t
+ ())
+(defknown %compare-and-swap-instance-ref (instance index t t) t
+ ())
+(defknown %compare-and-swap-symbol-value (symbol t t) t
+ (unwind))
+(defknown spin-loop-hint () (values)
+ (always-translatable))