diff --git a/doc/langref.html.in b/doc/langref.html.in
index cd1905ebfb8518afddb59e5a4aca3873cf45868a..6531323532e3c008ddf0dd9d819de9fc2e3fe840 100644
--- a/doc/langref.html.in
+++ b/doc/langref.html.in
@@ -8167,7 +8167,7 @@ test "vector @splat" {
       {#header_open|@tagName#}
       <pre>{#syntax#}@tagName(value: var) []const u8{#endsyntax#}</pre>
       <p>
-      Converts an enum value or union value to a slice of bytes representing the name.
+      Converts an enum value or union value to a slice of bytes representing the name. Not valid for unamed fields in non-exhaustive enums.
       </p>
       {#header_close#}