diff --git a/tests/basic_boot.rs b/tests/basic_boot.rs
index c409647e..4171eb7a 100644
--- a/tests/basic_boot.rs
+++ b/tests/basic_boot.rs
@@ -7,7 +7,7 @@
 use blog_os::println;
 use core::panic::PanicInfo;
 
-#[no_mangle] // don't mangle the name of this function
+#[unsafe(no_mangle)] // don't mangle the name of this function
 pub extern "C" fn _start() -> ! {
     test_main();
 
diff --git a/tests/should_panic.rs b/tests/should_panic.rs
index 375f51c0..f735259d 100644
--- a/tests/should_panic.rs
+++ b/tests/should_panic.rs
@@ -1,10 +1,10 @@
 #![no_std]
 #![no_main]
 
-use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
 use core::panic::PanicInfo;
 
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
     should_fail();
     serial_println!("[test did not panic]");
diff --git a/tests/stack_overflow.rs b/tests/stack_overflow.rs
index de826f38..1e97ae01 100644
--- a/tests/stack_overflow.rs
+++ b/tests/stack_overflow.rs
@@ -2,12 +2,12 @@
 #![no_main]
 #![feature(abi_x86_interrupt)]
 
-use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
 use core::panic::PanicInfo;
 use lazy_static::lazy_static;
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
 
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
     serial_print!("stack_overflow::stack_overflow...\t");