diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index 783b8b2db46..b8756d2526e 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -234,9 +234,9 @@ impl<'a, I: Iterator- >> Iterator for CodeBlocks<'_, 'a, I> {
return Some(Event::Html(
format!(
"",
- format!(" class=\"language-{}\"", lang),
+ lang,
Escape(&text),
)
.into(),