diff --git a/kernel/src/arch/x86_64/ipi.rs b/kernel/src/arch/x86_64/ipi.rs
index 3970272..abe6c08 100644
--- a/kernel/src/arch/x86_64/ipi.rs
+++ b/kernel/src/arch/x86_64/ipi.rs
@@ -1,12 +1,12 @@
 use crate::memory::phys_to_virt;
 /// Interface for inter-processor interrupt.
 /// This module wraps inter-processor interrupt into a broadcast-calling style.
-use alloc::boxed::{Box, FnBox};
+use alloc::boxed::{Box};
 use alloc::sync::Arc;
 use apic::{LocalApic, XApic, LAPIC_ADDR};
 use core::sync::atomic::{spin_loop_hint, AtomicU8, Ordering};
 
-pub type IPIEventItem = Box<FnBox()>;
+pub type IPIEventItem = Box<Fn()>;
 
 unsafe fn get_apic() -> XApic {
     let mut lapic = XApic::new(phys_to_virt(LAPIC_ADDR));
diff --git a/kernel/src/lib.rs b/kernel/src/lib.rs
index 8788476..54cc330 100644
--- a/kernel/src/lib.rs
+++ b/kernel/src/lib.rs
@@ -6,7 +6,6 @@
 #![feature(optin_builtin_traits)]
 #![feature(panic_info_message)]
 #![feature(global_asm)]
-#![feature(fnbox)]
 #![feature(maybe_uninit)]
 #![deny(unused_must_use)]
 #![no_std]
diff --git a/rust-toolchain b/rust-toolchain
index e37d6ad..e00fad6 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-nightly-2019-04-14
+nightly-2019-07-14