diff --git a/core/src/ffi/c_str.rs b/core/src/ffi/c_str.rs
index fbc0c7232c4e5..d2a408485d162 100644
--- a/core/src/ffi/c_str.rs
+++ b/core/src/ffi/c_str.rs
@@ -517,7 +517,8 @@ impl CStr {
     const fn as_non_null_ptr(&self) -> NonNull<c_char> {
         // FIXME(effects) replace with `NonNull::from`
         // SAFETY: a reference is never null
-        unsafe { NonNull::new_unchecked(&self.inner as *const [c_char] as *mut [c_char]) }.as_non_null_ptr()
+        unsafe { NonNull::new_unchecked(&self.inner as *const [c_char] as *mut [c_char]) }
+            .as_non_null_ptr()
     }
 
     /// Returns the length of `self`. Like C's `strlen`, this does not include the nul terminator.
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 51452e3b7b02f..2d0b8825f433b 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -200,6 +200,7 @@
 // Language features:
 // tidy-alphabetical-start
 #![cfg_attr(bootstrap, feature(c_unwind))]
+#![cfg_attr(bootstrap, feature(effects))]
 #![feature(abi_unadjusted)]
 #![feature(adt_const_params)]
 #![feature(allow_internal_unsafe)]