diff --git a/src/cmd/compile/internal/ir/expr.go b/src/cmd/compile/internal/ir/expr.go
index 7e7f8ac24b7..cea7c446d4a 100644
--- a/src/cmd/compile/internal/ir/expr.go
+++ b/src/cmd/compile/internal/ir/expr.go
@@ -181,7 +181,7 @@ func (n *BinaryExpr) SetOp(op Op) {
 	}
 }
 
-// A CallExpr is a function call X(Args).
+// A CallExpr is a function call Fun(Args).
 type CallExpr struct {
 	miniExpr
 	Fun       Node