diff --git a/src/header/signal/mod.rs b/src/header/signal/mod.rs
index 4ae70a032072889894f891c1b7427a98896556d9..f3b970c834620f490c10770d3df4374ce089de80 100644
--- a/src/header/signal/mod.rs
+++ b/src/header/signal/mod.rs
@@ -155,7 +155,7 @@ pub extern "C" fn sigfillset(set: *mut sigset_t) -> c_int {
     0
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn sighold(sig: c_int) -> c_int {
     let mut pset = mem::MaybeUninit::<sigset_t>::uninit();
     unsafe { sigemptyset(pset.as_mut_ptr()) };
@@ -166,7 +166,7 @@ pub extern "C" fn sighold(sig: c_int) -> c_int {
     sigprocmask(SIG_BLOCK, &set, ptr::null_mut())
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn sigignore(sig: c_int) -> c_int {
     let mut psa = mem::MaybeUninit::<sigaction>::uninit();
     unsafe { sigemptyset(&mut (*psa.as_mut_ptr()).sa_mask) };
@@ -176,7 +176,7 @@ pub extern "C" fn sigignore(sig: c_int) -> c_int {
     unsafe { sigaction(sig, &mut sa, ptr::null_mut()) }
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn siginterrupt(sig: c_int, flag: c_int) -> c_int {
     let mut psa = mem::MaybeUninit::<sigaction>::uninit();
     unsafe { sigaction(sig, ptr::null_mut(), psa.as_mut_ptr()) };
diff --git a/src/header/stdlib/mod.rs b/src/header/stdlib/mod.rs
index e16b03b4166502c98e44b2b50c6303ac7fae9f26..ad54751c3f2d252203924c93093cf938c82020a2 100644
--- a/src/header/stdlib/mod.rs
+++ b/src/header/stdlib/mod.rs
@@ -356,7 +356,7 @@ pub unsafe extern "C" fn getenv(name: *const c_char) -> *mut c_char {
     find_env(name).map(|val| val.1).unwrap_or(ptr::null_mut())
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub unsafe extern "C" fn getsubopt(
     optionp: *mut *mut c_char,
     tokens: *const *mut c_char,
@@ -1213,7 +1213,7 @@ pub extern "C" fn ttyslot() -> c_int {
     unimplemented!();
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub unsafe extern "C" fn unlockpt(fildes: c_int) -> c_int {
     let mut u: c_int = 0;
     ioctl(fildes, TIOCSPTLCK, &mut u as *mut i32 as *mut c_void)
diff --git a/src/header/unistd/mod.rs b/src/header/unistd/mod.rs
index 4847343dbdabd44ed111286c31d97d759f7c5e67..4859819457ec54a47a12a2451ddf11d618fbdcef 100644
--- a/src/header/unistd/mod.rs
+++ b/src/header/unistd/mod.rs
@@ -221,7 +221,7 @@ pub extern "C" fn fchdir(fildes: c_int) -> c_int {
     Sys::fchdir(fildes)
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn fdatasync(fildes: c_int) -> c_int {
     Sys::fdatasync(fildes)
 }
@@ -287,7 +287,7 @@ pub extern "C" fn getcwd(mut buf: *mut c_char, mut size: size_t) -> *mut c_char
     }
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn getdtablesize() -> c_int {
     let mut lim = mem::MaybeUninit::<sys_resource::rlimit>::uninit();
     let r = unsafe { sys_resource::getrlimit(sys_resource::RLIMIT_NOFILE as c_int, lim.as_mut_ptr() as *mut sys_resource::rlimit) };
@@ -645,7 +645,7 @@ pub unsafe extern "C" fn symlink(path1: *const c_char, path2: *const c_char) ->
     Sys::symlink(path1, path2)
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn sync() {
     Sys::sync();
 }