diff --git a/basis/compiler/cfg/rpo/rpo.factor b/basis/compiler/cfg/rpo/rpo.factor
index 09889c59d8..ec89853b7b 100644
--- a/basis/compiler/cfg/rpo/rpo.factor
+++ b/basis/compiler/cfg/rpo/rpo.factor
@@ -5,7 +5,7 @@ assocs fry compiler.cfg compiler.cfg.instructions ;
 FROM: namespaces => set ;
 IN: compiler.cfg.rpo
 
-: post-order-traversal ( visited bb -- visited' )
+: post-order-traversal ( visited bb -- visited )
     dup pick in? [ drop ] [
         dup pick adjoin
         [
diff --git a/basis/compiler/cfg/utilities/utilities.factor b/basis/compiler/cfg/utilities/utilities.factor
index 72bbcf4feb..9fdd771f61 100644
--- a/basis/compiler/cfg/utilities/utilities.factor
+++ b/basis/compiler/cfg/utilities/utilities.factor
@@ -18,7 +18,7 @@ IN: compiler.cfg.utilities
         [ first ##branch? ]
     } 1&& ;
 
-: (skip-empty-blocks) ( visited bb -- visited' bb' )
+: (skip-empty-blocks) ( visited bb -- visited bb' )
     dup pick in? [
         dup empty-block? [
             dup pick adjoin