add extra_traits

Author: StackOverflowExcept1on

src/unix/linux_like/android/b64/aarch64/mod.rs

@@ -99,6 +99,22 @@ s_no_extra_traits! {
     }
 }
 
+cfg_if! {
+    if #[cfg(feature = "extra_traits")] {
+        impl PartialEq for __c_anonymous_uc_sigmask {
+            fn eq(&self, other: &__c_anonymous_uc_sigmask) -> bool {
+                unsafe { self.uc_sigmask == other.uc_sigmask }
+            }
+        }
+        impl Eq for __c_anonymous_uc_sigmask {}
+        impl hash::Hash for __c_anonymous_uc_sigmask {
+            fn hash<H: hash::Hasher>(&self, state: &mut H) {
+                unsafe { self.uc_sigmask.hash(state) }
+            }
+        }
+    }
+}
+
 pub const O_DIRECT: c_int = 0x10000;
 pub const O_DIRECTORY: c_int = 0x4000;
 pub const O_NOFOLLOW: c_int = 0x8000;