try using #[cfg(bootstrap)]

Author: folkertdev

compiler-builtins/Cargo.toml

@@ -70,3 +70,6 @@ rustc-dep-of-std = ['compiler-builtins', 'core']
 # This makes certain traits and function specializations public that
 # are not normally public but are required by the `testcrate`
 public-test-deps = []
+
+[lints.rust]
+unexpected_cfgs = { level = "warn", check-cfg = ['cfg(bootstrap)'] }

compiler-builtins/src/aarch64.rs

@@ -3,7 +3,8 @@
 use core::intrinsics;
 
 intrinsics! {
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     #[cfg(all(target_os = "uefi", not(feature = "no-asm")))]
     pub unsafe extern "C" fn __chkstk() {
         core::arch::naked_asm!(

compiler-builtins/src/aarch64_linux.rs

@@ -131,7 +131,8 @@ macro_rules! compare_and_swap {
     ($ordering:ident, $bytes:tt, $name:ident) => {
         intrinsics! {
             #[maybe_use_optimized_c_shim]
-            #[unsafe(naked)]
+            #[cfg_attr(bootstrap, naked)]
+            #[cfg_attr(not(bootstrap), unsafe(naked))]
             pub unsafe extern "C" fn $name (
                 expected: int_ty!($bytes), desired: int_ty!($bytes), ptr: *mut int_ty!($bytes)
             ) -> int_ty!($bytes) {
@@ -161,7 +162,8 @@ macro_rules! compare_and_swap_i128 {
     ($ordering:ident, $name:ident) => {
         intrinsics! {
             #[maybe_use_optimized_c_shim]
-            #[unsafe(naked)]
+            #[cfg_attr(bootstrap, naked)]
+            #[cfg_attr(not(bootstrap), unsafe(naked))]
             pub unsafe extern "C" fn $name (
                 expected: i128, desired: i128, ptr: *mut i128
             ) -> i128 {
@@ -190,7 +192,8 @@ macro_rules! swap {
     ($ordering:ident, $bytes:tt, $name:ident) => {
         intrinsics! {
             #[maybe_use_optimized_c_shim]
-            #[unsafe(naked)]
+            #[cfg_attr(bootstrap, naked)]
+            #[cfg_attr(not(bootstrap), unsafe(naked))]
             pub unsafe extern "C" fn $name (
                 left: int_ty!($bytes), right_ptr: *mut int_ty!($bytes)
             ) -> int_ty!($bytes) {
@@ -215,7 +218,8 @@ macro_rules! fetch_op {
     ($ordering:ident, $bytes:tt, $name:ident, $op:literal) => {
         intrinsics! {
             #[maybe_use_optimized_c_shim]
-            #[unsafe(naked)]
+            #[cfg_attr(bootstrap, naked)]
+            #[cfg_attr(not(bootstrap), unsafe(naked))]
             pub unsafe extern "C" fn $name (
                 val: int_ty!($bytes), ptr: *mut int_ty!($bytes)
             ) -> int_ty!($bytes) {

compiler-builtins/src/arm.rs

@@ -20,7 +20,8 @@ macro_rules! bl {
 intrinsics! {
     // NOTE This function and the ones below are implemented using assembly because they are using a
     // custom calling convention which can't be implemented using a normal Rust function.
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     #[cfg(not(target_env = "msvc"))]
     pub unsafe extern "C" fn __aeabi_uidivmod() {
         core::arch::naked_asm!(
@@ -34,7 +35,8 @@ intrinsics! {
         );
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     pub unsafe extern "C" fn __aeabi_uldivmod() {
         core::arch::naked_asm!(
             "push {{r4, lr}}",
@@ -49,7 +51,8 @@ intrinsics! {
         );
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     pub unsafe extern "C" fn __aeabi_idivmod() {
         core::arch::naked_asm!(
             "push {{r0, r1, r4, lr}}",
@@ -61,7 +64,8 @@ intrinsics! {
         );
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     pub unsafe extern "C" fn __aeabi_ldivmod() {
         core::arch::naked_asm!(
             "push {{r4, lr}}",

compiler-builtins/src/int/udiv.rs

@@ -44,7 +44,8 @@ intrinsics! {
         ((rem as u64) << 32) | (div as u64)
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     pub unsafe extern "C" fn __udivmodqi4() {
         // compute unsigned 8-bit `n / d` and `n % d`.
         //
@@ -79,7 +80,8 @@ intrinsics! {
         );
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     pub unsafe extern "C" fn __udivmodhi4() {
         // compute unsigned 16-bit `n / d` and `n % d`.
         //

compiler-builtins/src/macros.rs

@@ -423,7 +423,8 @@ macro_rules! intrinsics {
     // Naked functions are special: we can't generate wrappers for them since
     // they use a custom calling convention.
     (
-        #[unsafe(naked)]
+        #[cfg_attr(bootstrap, naked)]
+        #[cfg_attr(not(bootstrap), unsafe(naked))]
         $(#[$($attr:tt)*])*
         pub unsafe extern $abi:tt fn $name:ident( $($argname:ident:  $ty:ty),* ) $(-> $ret:ty)? {
             $($body:tt)*
@@ -433,7 +434,8 @@ macro_rules! intrinsics {
     ) => (
         // `#[naked]` definitions are referenced by other places, so we can't use `cfg` like the others
         pub mod $name {
-            #[unsafe(naked)]
+            #[cfg_attr(bootstrap, naked)]
+            #[cfg_attr(not(bootstrap), unsafe(naked))]
             $(#[$($attr)*])*
             #[cfg_attr(not(feature = "mangled-names"), no_mangle)]
             #[cfg_attr(not(any(all(windows, target_env = "gnu"), target_os = "cygwin")), linkage = "weak")]

compiler-builtins/src/x86.rs

@@ -8,7 +8,8 @@ use core::intrinsics;
 // NOTE These functions are never mangled as they are not tested against compiler-rt
 
 intrinsics! {
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     #[cfg(all(
         any(all(windows, target_env = "gnu"), target_os = "uefi"),
         not(feature = "no-asm")
@@ -20,7 +21,8 @@ intrinsics! {
         );
     }
 
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     #[cfg(all(
         any(all(windows, target_env = "gnu"), target_os = "uefi"),
         not(feature = "no-asm")

compiler-builtins/src/x86_64.rs

@@ -8,7 +8,8 @@ use core::intrinsics;
 // NOTE These functions are never mangled as they are not tested against compiler-rt
 
 intrinsics! {
-    #[unsafe(naked)]
+    #[cfg_attr(bootstrap, naked)]
+    #[cfg_attr(not(bootstrap), unsafe(naked))]
     #[cfg(all(
         any(
             all(windows, target_env = "gnu"),