fix: mark extern blocks as unsafe

src/arch/aarch64/kernel/start.rs

@@ -6,7 +6,7 @@ use hermit_entry::Entry;
 use crate::arch::aarch64::kernel::scheduler::TaskStacks;
 use crate::{env, KERNEL_STACK_SIZE};
 
-extern "C" {
+unsafe extern "C" {
 	static vector_table: u8;
 }
 

src/arch/riscv64/kernel/scheduler.rs

@@ -420,7 +420,7 @@ impl TaskFrame for Task {
 	}
 }
 
-extern "C" {
+unsafe extern "C" {
 	fn task_start(func: extern "C" fn(usize), arg: usize, user_stack: u64);
 }
 

src/arch/riscv64/kernel/switch.rs

@@ -2,6 +2,6 @@ use core::arch::global_asm;
 
 global_asm!(include_str!("switch.s"));
 
-extern "C" {
+unsafe extern "C" {
 	pub fn switch_to_task(old_stack: *mut usize, new_stack: usize);
 }

src/lib.rs

@@ -116,7 +116,7 @@ fn trivial_test() {
 /// Entry point of a kernel thread, which initialize the libos
 #[cfg(target_os = "none")]
 extern "C" fn initd(_arg: usize) {
-	extern "C" {
+	unsafe extern "C" {
 		#[cfg(all(not(test), not(any(feature = "nostd", feature = "common-os"))))]
 		fn runtime_entry(argc: i32, argv: *const *const u8, env: *const *const u8) -> !;
 		#[cfg(all(not(test), any(feature = "nostd", feature = "common-os")))]
@@ -190,7 +190,7 @@ fn boot_processor_main() -> ! {
 		info!("FDT:\n{fdt:#?}");
 	}
 
-	extern "C" {
+	unsafe extern "C" {
 		static mut __bss_start: u8;
 	}
 	let bss_ptr = core::ptr::addr_of_mut!(__bss_start);

tests/basic_mem.rs

@@ -22,7 +22,7 @@ where
 	T: core::fmt::Debug,
 	T: num_traits::int::PrimInt,
 {
-	extern "C" {
+	unsafe extern "C" {
 		fn memcpy(dest: *mut u8, src: *const u8, n: usize) -> *mut u8;
 		fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> i32;
 	}