diff --git a/src/libsyntax/ext/env.rs b/src/libsyntax/ext/env.rs
index cd7fbb4fa73a..63d563adf267 100644
--- a/src/libsyntax/ext/env.rs
+++ b/src/libsyntax/ext/env.rs
@@ -108,7 +108,7 @@ pub fn expand_env<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
             cx.span_err(sp, msg.deref());
             cx.expr_usize(sp, 0)
         }
-        Ok(s) => cx.expr_str(sp, token::intern_and_get_ident(&s[]))
+        Some(s) => cx.expr_str(sp, token::intern_and_get_ident(&s[]))
     };
     MacExpr::new(e)
 }