diff --git a/src/libboard_artiq/src/lib.rs b/src/libboard_artiq/src/lib.rs
index b70ec4d..aeca82d 100644
--- a/src/libboard_artiq/src/lib.rs
+++ b/src/libboard_artiq/src/lib.rs
@@ -1,7 +1,7 @@
 #![no_std]
 #![feature(never_type)]
 #![feature(naked_functions)]
-#![feature(asm)]
+#![allow(unexpected_cfgs)]
 
 extern crate crc;
 extern crate embedded_hal;
diff --git a/src/libbuild_zynq/lib.rs b/src/libbuild_zynq/lib.rs
index ab31b06..afebb67 100644
--- a/src/libbuild_zynq/lib.rs
+++ b/src/libbuild_zynq/lib.rs
@@ -1,3 +1,5 @@
+#![allow(unexpected_cfgs)]
+
 use std::{env,
           fs::File,
           io::{BufRead, BufReader, Write},
diff --git a/src/libio/lib.rs b/src/libio/lib.rs
index ed115ac..f0c9fcb 100644
--- a/src/libio/lib.rs
+++ b/src/libio/lib.rs
@@ -1,5 +1,6 @@
 #![no_std]
 #![feature(never_type)]
+#![allow(unexpected_cfgs)]
 
 #[cfg(feature = "alloc")]
 extern crate alloc;
diff --git a/src/libksupport/src/eh_rust.rs b/src/libksupport/src/eh_rust.rs
index 236992e..3370a0c 100644
--- a/src/libksupport/src/eh_rust.rs
+++ b/src/libksupport/src/eh_rust.rs
@@ -15,9 +15,9 @@
 // By design, this personality function is only ever called in the search phase, although
 // to keep things simple and close to upstream, it is not modified
 use unwind as uw;
-use libc::{c_int, uintptr_t};
+use libc::c_int;
 
-use dwarf::eh::{self, EHAction, EHContext};
+use dwarf::eh::{EHAction, EHContext};
 
 // Register ids were lifted from LLVM's TargetLowering::getExceptionPointerRegister()
 // and TargetLowering::getExceptionSelectorRegister() for each architecture,
diff --git a/src/libksupport/src/lib.rs b/src/libksupport/src/lib.rs
index 7cd6303..7f978d4 100644
--- a/src/libksupport/src/lib.rs
+++ b/src/libksupport/src/lib.rs
@@ -2,9 +2,8 @@
 #![feature(c_variadic)]
 #![feature(const_btree_len)]
 #![feature(lang_items)]
-#![feature(generic_const_exprs)]
 #![feature(naked_functions)]
-#![feature(asm)]
+#![allow(unexpected_cfgs)]
 
 #[macro_use]
 extern crate alloc;
diff --git a/src/libksupport/src/rpc.rs b/src/libksupport/src/rpc.rs
index 85825ec..45c8dc2 100644
--- a/src/libksupport/src/rpc.rs
+++ b/src/libksupport/src/rpc.rs
@@ -57,7 +57,6 @@ where
             let ptr = storage as *mut u32;
             let dest = core::slice::from_raw_parts_mut(ptr as *mut u8, length * 4);
             reader.read_exact(dest)?;
-            drop(dest);
             let dest = core::slice::from_raw_parts_mut(ptr, length);
             NativeEndian::from_slice_u32(dest);
         }
@@ -65,7 +64,6 @@ where
             let ptr = storage as *mut u64;
             let dest = core::slice::from_raw_parts_mut(ptr as *mut u8, length * 8);
             reader.read_exact(dest)?;
-            drop(dest);
             let dest = core::slice::from_raw_parts_mut(ptr, length);
             NativeEndian::from_slice_u64(dest);
         }
diff --git a/src/runtime/build.rs b/src/runtime/build.rs
index aee092b..557db0a 100644
--- a/src/runtime/build.rs
+++ b/src/runtime/build.rs
@@ -1,3 +1,4 @@
+#![allow(unexpected_cfgs)]
 extern crate build_zynq;
 
 fn main() {
diff --git a/src/runtime/src/main.rs b/src/runtime/src/main.rs
index dd24e25..3c19273 100644
--- a/src/runtime/src/main.rs
+++ b/src/runtime/src/main.rs
@@ -1,9 +1,9 @@
 #![no_std]
 #![no_main]
 #![recursion_limit = "1024"] // for futures_util::select!
+#![allow(unexpected_cfgs)]
 #![feature(alloc_error_handler)]
-#![feature(const_btree_new)]
-#![feature(panic_info_message)]
+#![feature(const_btree_len)]
 
 #[macro_use]
 extern crate alloc;
diff --git a/src/runtime/src/rpc_async.rs b/src/runtime/src/rpc_async.rs
index 303c630..25d17cd 100644
--- a/src/runtime/src/rpc_async.rs
+++ b/src/runtime/src/rpc_async.rs
@@ -38,7 +38,6 @@ where
             let ptr = storage as *mut u32;
             let dest = core::slice::from_raw_parts_mut(ptr as *mut u8, length * 4);
             proto_async::read_chunk(stream, dest).await?;
-            drop(dest);
             let dest = core::slice::from_raw_parts_mut(ptr, length);
             NativeEndian::from_slice_u32(dest);
         }
@@ -46,7 +45,6 @@ where
             let ptr = storage as *mut u64;
             let dest = core::slice::from_raw_parts_mut(ptr as *mut u8, length * 8);
             proto_async::read_chunk(stream, dest).await?;
-            drop(dest);
             let dest = core::slice::from_raw_parts_mut(ptr, length);
             NativeEndian::from_slice_u64(dest);
         }
diff --git a/src/satman/src/main.rs b/src/satman/src/main.rs
index dd63c5f..d97ce72 100644
--- a/src/satman/src/main.rs
+++ b/src/satman/src/main.rs
@@ -1,6 +1,7 @@
 #![no_std]
 #![no_main]
 #![feature(alloc_error_handler, never_type)]
+#![allow(unexpected_cfgs)]
 
 #[macro_use]
 extern crate log;
@@ -1457,7 +1458,7 @@ pub fn panic_fmt(info: &core::panic::PanicInfo) -> ! {
     } else {
         print!("unknown location");
     }
-    if let Some(message) = info.message() {
+    if let Some(message) = info.message().as_str() {
         println!(": {}", message);
     } else {
         println!("");