diff --git a/tests/ui/lint/cli-lint-override.forbid_warn.stderr b/tests/ui/lint/cli-lint-override.forbid_warn.stderr
index d8c75c33b0c56..f257deaf21afe 100644
--- a/tests/ui/lint/cli-lint-override.forbid_warn.stderr
+++ b/tests/ui/lint/cli-lint-override.forbid_warn.stderr
@@ -2,9 +2,10 @@ error: extern declarations without an explicit ABI are deprecated
   --> $DIR/cli-lint-override.rs:12:1
    |
 LL | extern fn foo() {}
-   | ^^^^^^^^^^^^^^^ ABI should be specified here
+   | ^^^^^^ help: explicitly specify the C ABI: `extern "C"`
    |
-   = help: the default ABI is C
+   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2024!
+   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2024/explicit-abi.html>
    = note: requested on the command line with `-F missing-abi`
 
 error: aborting due to 1 previous error
diff --git a/tests/ui/lint/cli-lint-override.force_warn_deny.stderr b/tests/ui/lint/cli-lint-override.force_warn_deny.stderr
index 779c24c93f245..89279d04fa14e 100644
--- a/tests/ui/lint/cli-lint-override.force_warn_deny.stderr
+++ b/tests/ui/lint/cli-lint-override.force_warn_deny.stderr
@@ -2,9 +2,10 @@ warning: extern declarations without an explicit ABI are deprecated
   --> $DIR/cli-lint-override.rs:12:1
    |
 LL | extern fn foo() {}
-   | ^^^^^^^^^^^^^^^ ABI should be specified here
+   | ^^^^^^ help: explicitly specify the C ABI: `extern "C"`
    |
-   = help: the default ABI is C
+   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2024!
+   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2024/explicit-abi.html>
    = note: requested on the command line with `--force-warn missing-abi`
 
 warning: 1 warning emitted
diff --git a/tests/ui/lint/cli-lint-override.rs b/tests/ui/lint/cli-lint-override.rs
index 4b3fd0d9c01c9..d0223046e06bf 100644
--- a/tests/ui/lint/cli-lint-override.rs
+++ b/tests/ui/lint/cli-lint-override.rs
@@ -13,5 +13,6 @@ extern fn foo() {}
 //[warn_deny]~^ ERROR extern declarations without an explicit ABI are deprecated
 //[forbid_warn]~^^ ERROR extern declarations without an explicit ABI are deprecated
 //[force_warn_deny]~^^^ WARN extern declarations without an explicit ABI are deprecated
+//~^^^^ WARN edition
 
 fn main() {}
diff --git a/tests/ui/lint/cli-lint-override.warn_deny.stderr b/tests/ui/lint/cli-lint-override.warn_deny.stderr
index 1ba42e9ce3234..590bc89f7b40f 100644
--- a/tests/ui/lint/cli-lint-override.warn_deny.stderr
+++ b/tests/ui/lint/cli-lint-override.warn_deny.stderr
@@ -2,9 +2,10 @@ error: extern declarations without an explicit ABI are deprecated
   --> $DIR/cli-lint-override.rs:12:1
    |
 LL | extern fn foo() {}
-   | ^^^^^^^^^^^^^^^ ABI should be specified here
+   | ^^^^^^ help: explicitly specify the C ABI: `extern "C"`
    |
-   = help: the default ABI is C
+   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2024!
+   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2024/explicit-abi.html>
    = note: requested on the command line with `-D missing-abi`
 
 error: aborting due to 1 previous error
diff --git a/tests/ui/unpretty/expanded-exhaustive.rs b/tests/ui/unpretty/expanded-exhaustive.rs
index 799e8071d028a..39ee25934c99e 100644
--- a/tests/ui/unpretty/expanded-exhaustive.rs
+++ b/tests/ui/unpretty/expanded-exhaustive.rs
@@ -452,15 +452,15 @@ mod items {
     /// ItemKind::Fn
     mod item_fn {
         pub const unsafe extern "C" fn f() {}
-        pub async unsafe extern fn g() {}
+        pub async unsafe extern "C" fn g() {}
         fn h<'a, T>() where T: 'a {}
 
         trait TraitItems {
-            unsafe extern fn f();
+            unsafe extern "C" fn f();
         }
 
         impl TraitItems for _ {
-            default unsafe extern fn f() {}
+            default unsafe extern "C" fn f() {}
         }
     }
 
@@ -472,7 +472,7 @@ mod items {
     /// ItemKind::ForeignMod
     mod item_foreign_mod {
         unsafe extern "C++" {}
-        unsafe extern {}
+        unsafe extern "C" {}
     }
 
     /// ItemKind::GlobalAsm
diff --git a/tests/ui/unpretty/expanded-exhaustive.stdout b/tests/ui/unpretty/expanded-exhaustive.stdout
index d8384951e12f0..34b55368fbdef 100644
--- a/tests/ui/unpretty/expanded-exhaustive.stdout
+++ b/tests/ui/unpretty/expanded-exhaustive.stdout
@@ -433,13 +433,13 @@ mod items {
     /// ItemKind::Fn
     mod item_fn {
         pub const unsafe extern "C" fn f() {}
-        pub async unsafe extern fn g() {}
+        pub async unsafe extern "C" fn g() {}
         fn h<'a, T>() where T: 'a {}
         trait TraitItems {
-            unsafe extern fn f();
+            unsafe extern "C" fn f();
         }
         impl TraitItems for _ {
-            default unsafe extern fn f() {}
+            default unsafe extern "C" fn f() {}
         }
     }
     /// ItemKind::Mod
@@ -447,7 +447,7 @@ mod items {
     /// ItemKind::ForeignMod
     mod item_foreign_mod {
         unsafe extern "C++" {}
-        unsafe extern {}
+        unsafe extern "C" {}
     }
     /// ItemKind::GlobalAsm
     mod item_global_asm {