diff --git a/library/std/src/os/solid/io.rs b/library/std/src/os/solid/io.rs
index 19b4fe22093c3..e75bcf74e5cd3 100644
--- a/library/std/src/os/solid/io.rs
+++ b/library/std/src/os/solid/io.rs
@@ -44,7 +44,6 @@
 //!
 //! [`BorrowedFd<'a>`]: crate::os::solid::io::BorrowedFd
 
-#![deny(unsafe_op_in_unsafe_fn)]
 #![unstable(feature = "solid_ext", issue = "none")]
 
 use crate::fmt;
diff --git a/library/std/src/os/solid/mod.rs b/library/std/src/os/solid/mod.rs
index 0bb83c73ddf7c..75824048e2498 100644
--- a/library/std/src/os/solid/mod.rs
+++ b/library/std/src/os/solid/mod.rs
@@ -1,4 +1,5 @@
 #![stable(feature = "rust1", since = "1.0.0")]
+#![forbid(unsafe_op_in_unsafe_fn)]
 
 pub mod ffi;
 pub mod io;
diff --git a/library/std/src/sys/pal/solid/mod.rs b/library/std/src/sys/pal/solid/mod.rs
index 9a7741ddda71e..0b158fb63df70 100644
--- a/library/std/src/sys/pal/solid/mod.rs
+++ b/library/std/src/sys/pal/solid/mod.rs
@@ -1,6 +1,6 @@
 #![allow(dead_code)]
 #![allow(missing_docs, nonstandard_style)]
-#![deny(unsafe_op_in_unsafe_fn)]
+#![forbid(unsafe_op_in_unsafe_fn)]
 
 pub mod abi;
 
diff --git a/library/std/src/sys/path/unsupported_backslash.rs b/library/std/src/sys/path/unsupported_backslash.rs
index 7045c9be25b08..855f443678c6c 100644
--- a/library/std/src/sys/path/unsupported_backslash.rs
+++ b/library/std/src/sys/path/unsupported_backslash.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_op_in_unsafe_fn)]
 use crate::ffi::OsStr;
 use crate::io;
 use crate::path::{Path, PathBuf, Prefix};
diff --git a/library/std/src/sys/sync/mutex/itron.rs b/library/std/src/sys/sync/mutex/itron.rs
index 4ba32a8fbcd69..b29c7e1d03444 100644
--- a/library/std/src/sys/sync/mutex/itron.rs
+++ b/library/std/src/sys/sync/mutex/itron.rs
@@ -1,5 +1,6 @@
 //! Mutex implementation backed by μITRON mutexes. Assumes `acre_mtx` and
 //! `TA_INHERIT` are available.
+#![forbid(unsafe_op_in_unsafe_fn)]
 
 use crate::sys::pal::itron::{
     abi,
diff --git a/library/std/src/sys/sync/rwlock/solid.rs b/library/std/src/sys/sync/rwlock/solid.rs
index 7558eee8edd33..a8fef685ceb27 100644
--- a/library/std/src/sys/sync/rwlock/solid.rs
+++ b/library/std/src/sys/sync/rwlock/solid.rs
@@ -1,4 +1,5 @@
 //! A readers-writer lock implementation backed by the SOLID kernel extension.
+#![forbid(unsafe_op_in_unsafe_fn)]
 
 use crate::sys::pal::{
     abi,