3 files changed, 5 insertions, 5 deletions
diff --git a/library/coretests/tests/mem.rs b/library/coretests/tests/mem.rs
index 1b5c5fc82a6..9cb94ca3b0f 100644
--- a/library/coretests/tests/mem.rs
+++ b/library/coretests/tests/mem.rs
@@ -648,7 +648,7 @@ fn offset_of_dst() {
         z: dyn Trait,
     }
 
-    extern "C" {
+    unsafe extern "C" {
         type Extern;
     }
 
diff --git a/library/coretests/tests/num/flt2dec/mod.rs b/library/coretests/tests/num/flt2dec/mod.rs
index 3d825224813..6041923117c 100644
--- a/library/coretests/tests/num/flt2dec/mod.rs
+++ b/library/coretests/tests/num/flt2dec/mod.rs
@@ -80,7 +80,7 @@ fn ldexp_f32(a: f32, b: i32) -> f32 {
 }
 
 fn ldexp_f64(a: f64, b: i32) -> f64 {
-    extern "C" {
+    unsafe extern "C" {
         fn ldexp(x: f64, n: i32) -> f64;
     }
     // SAFETY: assuming a correct `ldexp` has been supplied, the given arguments cannot possibly
diff --git a/library/coretests/tests/ptr.rs b/library/coretests/tests/ptr.rs
index 345bec345d1..0c9f9b338b0 100644
--- a/library/coretests/tests/ptr.rs
+++ b/library/coretests/tests/ptr.rs
@@ -97,7 +97,7 @@ fn test_is_null() {
     let nmi: *mut dyn ToString = null_mut::<isize>();
     assert!(nmi.is_null());
 
-    extern "C" {
+    unsafe extern "C" {
         type Extern;
     }
     let ec: *const Extern = null::<Extern>();
@@ -308,7 +308,7 @@ fn test_const_nonnull_new() {
 pub fn test_variadic_fnptr() {
     use core::ffi;
     use core::hash::{Hash, SipHasher};
-    extern "C" {
+    unsafe extern "C" {
         // This needs to use the correct function signature even though it isn't called as some
         // codegen backends make it UB to declare a function with multiple conflicting signatures
         // (like LLVM) while others straight up return an error (like Cranelift).
@@ -506,7 +506,7 @@ fn offset_from() {
 fn ptr_metadata() {
     struct Unit;
     struct Pair<A, B: ?Sized>(A, B);
-    extern "C" {
+    unsafe extern "C" {
         type Extern;
     }
     let () = metadata(&());