diff --git a/tests/ui/lto/lto-avx-target-feature.rs b/tests/ui/lto/lto-avx-target-feature.rs
index 37d7b00cf7f0..37a8ce67dcfc 100644
--- a/tests/ui/lto/lto-avx-target-feature.rs
+++ b/tests/ui/lto/lto-avx-target-feature.rs
@@ -1,3 +1,4 @@
+//! regression test for <https://github.com/rust-lang/rust/issues/44056>
 //@ build-pass (FIXME(55996): should be run on targets supporting avx)
 //@ only-x86_64
 //@ no-prefer-dynamic
diff --git a/tests/ui/lto/lto-weak-merge-functions.rs b/tests/ui/lto/lto-weak-merge-functions.rs
index eda48aa5cf47..bf16fbc83435 100644
--- a/tests/ui/lto/lto-weak-merge-functions.rs
+++ b/tests/ui/lto/lto-weak-merge-functions.rs
@@ -1,3 +1,4 @@
+//! regression test for <https://github.com/rust-lang/rust/issues/51947>
 //@ build-pass
 
 #![crate_type = "lib"]