2 files changed, 4 insertions, 0 deletions
diff --git a/src/libserialize/base64.rs b/src/libserialize/base64.rs
index 79c1d655411..5e8648d355e 100644
--- a/src/libserialize/base64.rs
+++ b/src/libserialize/base64.rs
@@ -7,6 +7,8 @@
 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
+//
+// ignore-lexer-test FIXME #15679
 
 //! Base64 binary-to-text encoding
 use std::str;
diff --git a/src/libserialize/hex.rs b/src/libserialize/hex.rs
index 3083c06c877..d6a029c583c 100644
--- a/src/libserialize/hex.rs
+++ b/src/libserialize/hex.rs
@@ -7,6 +7,8 @@
 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
+//
+// ignore-lexer-test FIXME #15679
 
 //! Hex binary-to-text encoding
 use std::str;