try to make cfg work for ptp_perout_request

Author: folkertdev

Diff for: libc-test/build.rs

@@ -4266,7 +4266,11 @@ fn test_linux(target: &str) {
         // `__exit_status` type is a patch which is absent in musl
         (struct_ == "utmpx" && field == "ut_exit" && musl) ||
         // `can_addr` is an anonymous union
-        (struct_ == "sockaddr_can" && field == "can_addr")
+        (struct_ == "sockaddr_can" && field == "can_addr") ||
+        // `anonymous_1` is an anonymous union
+        (struct_ == "ptp_perout_request" && field == "anonymous_1") ||
+        // `anonymous_2` is an anonymous union
+        (struct_ == "ptp_perout_request" && field == "anonymous_2")
     });
 
     cfg.volatile_item(|i| {

Diff for: src/unix/linux_like/linux/mod.rs

@@ -676,13 +676,6 @@ s! {
         pub rsv: [::c_uint; 2],
     }
 
-    pub struct ptp_perout_request {
-        pub anonymous_1: __c_anonymous_ptp_perout_request_1,
-        pub period: ptp_clock_time,
-        pub index: ::c_uint,
-        pub flags: ::c_uint,
-        pub anonymous_2: __c_anonymous_ptp_perout_request_2,
-    }
 
     pub struct ptp_sys_offset {
         pub n_samples: ::c_uint,
@@ -958,18 +951,6 @@ s_no_extra_traits! {
         pub sched_period: ::__u64,
     }
 
-    // linux/ptp_clock.h
-    #[cfg(libc_union)]
-    pub union __c_anonymous_ptp_perout_request_1 {
-        pub start: ptp_clock_time,
-        pub phase: ptp_clock_time,
-    }
-
-    #[cfg(libc_union)]
-    pub union __c_anonymous_ptp_perout_request_2 {
-        pub on: ptp_clock_time,
-        pub rsv: [::c_uint; 4],
-    }
 }
 
 s_no_extra_traits! {
@@ -997,6 +978,35 @@ cfg_if! {
                 pub can_ifindex: ::c_int,
                 pub can_addr: __c_anonymous_sockaddr_can_can_addr,
             }
+
+        }
+    }
+}
+
+cfg_if! {
+    if #[cfg(libc_union)] {
+        s_no_extra_traits! {
+            // linux/ptp_clock.h
+            #[allow(missing_debug_implementations)]
+            pub union __c_anonymous_ptp_perout_request_1 {
+                pub start: ptp_clock_time,
+                pub phase: ptp_clock_time,
+            }
+
+            #[allow(missing_debug_implementations)]
+            pub union __c_anonymous_ptp_perout_request_2 {
+                pub on: ptp_clock_time,
+                pub rsv: [::c_uint; 4],
+            }
+
+            #[allow(missing_debug_implementations)]
+            pub struct ptp_perout_request {
+                pub anonymous_1: __c_anonymous_ptp_perout_request_1,
+                pub period: ptp_clock_time,
+                pub index: ::c_uint,
+                pub flags: ::c_uint,
+                pub anonymous_2: __c_anonymous_ptp_perout_request_2,
+            }
         }
     }
 }