cleanup: Remove the const_fn! macro

Now that is okay for functions to be always `const`, this macro doesn't
add anything other than the `#[inline]` attribute, which isn't useful
for private functions anyway. Thus, remove the macro and leave its
contents wherever it is used.

(backport <#4714>)
(cherry picked from commit dcde5cd)

Author: tgross35

src/macros.rs

@@ -330,20 +330,6 @@ macro_rules! safe_f {
     )+};
 }
 
-/// Define a nonpublic function.
-macro_rules! const_fn {
-    ($(
-        $(#[$attr:meta])*
-        const fn $i:ident($($arg:ident: $argty:ty),* $(,)*) -> $ret:ty
-            $body:block
-    )*) => ($(
-        #[inline]
-        $(#[$attr])*
-        const fn $i($($arg: $argty),*) -> $ret
-            $body
-    )*)
-}
-
 macro_rules! __item {
     ($i:item) => {
         $i

src/unix/bsd/freebsdlike/dragonfly/mod.rs

@@ -1419,10 +1419,8 @@ pub const RTAX_MPLS2: c_int = 9;
 pub const RTAX_MPLS3: c_int = 10;
 pub const RTAX_MAX: c_int = 11;
 
-const_fn! {
-    const fn _CMSG_ALIGN(n: usize) -> usize {
-        (n + (size_of::<c_long>() - 1)) & !(size_of::<c_long>() - 1)
-    }
+const fn _CMSG_ALIGN(n: usize) -> usize {
+    (n + (size_of::<c_long>() - 1)) & !(size_of::<c_long>() - 1)
 }
 
 f! {

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -4749,10 +4749,8 @@ pub const fn MAP_ALIGNED(a: c_int) -> c_int {
     a << 24
 }
 
-const_fn! {
-    const fn _ALIGN(p: usize) -> usize {
-        (p + _ALIGNBYTES) & !_ALIGNBYTES
-    }
+const fn _ALIGN(p: usize) -> usize {
+    (p + _ALIGNBYTES) & !_ALIGNBYTES
 }
 
 f! {

src/unix/bsd/netbsdlike/netbsd/mod.rs

@@ -2301,10 +2301,8 @@ pub const TFD_NONBLOCK: i32 = crate::O_NONBLOCK;
 pub const TFD_TIMER_ABSTIME: i32 = crate::O_WRONLY;
 pub const TFD_TIMER_CANCEL_ON_SET: i32 = crate::O_RDWR;
 
-const_fn! {
-    const fn _ALIGN(p: usize) -> usize {
-        (p + _ALIGNBYTES) & !_ALIGNBYTES
-    }
+const fn _ALIGN(p: usize) -> usize {
+    (p + _ALIGNBYTES) & !_ALIGNBYTES
 }
 
 f! {

src/unix/bsd/netbsdlike/openbsd/mod.rs

@@ -1868,10 +1868,8 @@ pub const RTAX_STATIC: c_int = 13;
 pub const RTAX_SEARCH: c_int = 14;
 pub const RTAX_MAX: c_int = 15;
 
-const_fn! {
-    const fn _ALIGN(p: usize) -> usize {
-        (p + _ALIGNBYTES) & !_ALIGNBYTES
-    }
+const fn _ALIGN(p: usize) -> usize {
+    (p + _ALIGNBYTES) & !_ALIGNBYTES
 }
 
 f! {

src/unix/cygwin/mod.rs

@@ -1928,10 +1928,8 @@ safe_f! {
     }
 }
 
-const_fn! {
-    const fn CMSG_ALIGN(len: usize) -> usize {
-        len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
-    }
+const fn CMSG_ALIGN(len: usize) -> usize {
+    len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
 }
 
 extern "C" {

src/unix/haiku/mod.rs

@@ -1514,10 +1514,8 @@ pub const POSIX_SPAWN_SETSIGDEF: c_int = 0x10;
 pub const POSIX_SPAWN_SETSIGMASK: c_int = 0x20;
 pub const POSIX_SPAWN_SETSID: c_int = 0x40;
 
-const_fn! {
-    const fn CMSG_ALIGN(len: usize) -> usize {
-        len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
-    }
+const fn CMSG_ALIGN(len: usize) -> usize {
+    len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
 }
 
 f! {

src/unix/hurd/mod.rs

@@ -3414,10 +3414,8 @@ pub const PTHREAD_STACK_MIN: size_t = 0;
 // Non-public helper constants
 const _UTSNAME_LENGTH: usize = 1024;
 
-const_fn! {
-    const fn CMSG_ALIGN(len: usize) -> usize {
-        (len + size_of::<usize>() - 1) & !(size_of::<usize>() - 1)
-    }
+const fn CMSG_ALIGN(len: usize) -> usize {
+    (len + size_of::<usize>() - 1) & !(size_of::<usize>() - 1)
 }
 
 // functions

src/unix/linux_like/mod.rs

@@ -1784,10 +1784,8 @@ cfg_if! {
     }
 }
 
-const_fn! {
-    const fn CMSG_ALIGN(len: usize) -> usize {
-        (len + size_of::<usize>() - 1) & !(size_of::<usize>() - 1)
-    }
+const fn CMSG_ALIGN(len: usize) -> usize {
+    (len + size_of::<usize>() - 1) & !(size_of::<usize>() - 1)
 }
 
 f! {

src/unix/nto/mod.rs

@@ -2607,14 +2607,12 @@ pub const PTHREAD_RWLOCK_INITIALIZER: pthread_rwlock_t = pthread_rwlock_t {
     __spare: 0,
 };
 
-const_fn! {
-    const fn _CMSG_ALIGN(len: usize) -> usize {
-        len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
-    }
+const fn _CMSG_ALIGN(len: usize) -> usize {
+    len + size_of::<usize>() - 1 & !(size_of::<usize>() - 1)
+}
 
-    const fn _ALIGN(p: usize, b: usize) -> usize {
-        (p + b - 1) & !(b - 1)
-    }
+const fn _ALIGN(p: usize, b: usize) -> usize {
+    (p + b - 1) & !(b - 1)
 }
 
 f! {