diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index b966fd9..5a7e6ec 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -12236,6 +12236,7 @@
 multi_byte_ime		Compiled with support for IME input method.
 multi_lang		Compiled with support for multiple languages.
 mzscheme		Compiled with MzScheme interface |mzscheme|.
+nanotime		Compiled with sub-second time stamp checks.
 netbeans_enabled	Compiled with support for |netbeans| and connected.
 netbeans_intg		Compiled with support for |netbeans|.
 num64			Compiled with 64-bit |Number| support.