Fixed UB in setsockopt_option_scalar

* Also whitelisted some clippy dead_code warnings.

libzmq/src/core/sockopt.rs

@@ -16,6 +16,7 @@ use std::{
 const MAX_OPTION_SIZE: size_t = 255;
 
 #[derive(Copy, Clone, Debug)]
+#[allow(dead_code)]
 pub(crate) enum SocketOption {
     Backlog = sys::ZMQ_BACKLOG as isize,
     ConnectTimeout = sys::ZMQ_CONNECT_TIMEOUT as isize,
@@ -262,11 +263,16 @@ where
 {
     let size = mem::size_of::<T>() as size_t;
 
-    let value_ptr = match maybe {
-        Some(value) => &value as *const T as *const c_void,
-        None => &none_value as *const T as *const c_void,
-    };
-    setsockopt(mut_sock_ptr, option, value_ptr, size)
+    match maybe {
+        Some(value) => {
+            let value_ptr = &value as *const T as *const c_void;
+            setsockopt(mut_sock_ptr, option, value_ptr, size)
+        }
+        None => {
+            let value_ptr = &none_value as *const T as *const c_void;
+            setsockopt(mut_sock_ptr, option, value_ptr, size)
+        }
+    }
 }
 
 pub(crate) fn setsockopt_bytes(
@@ -311,6 +317,8 @@ pub(crate) fn setsockopt_option_duration(
         check_duration(duration)?;
     }
 
+    dbg!(option, maybe);
+
     setsockopt_option_scalar(
         mut_sock_ptr,
         option,

libzmq/src/ctx.rs

@@ -17,6 +17,7 @@ lazy_static! {
 }
 
 #[derive(Copy, Clone, Debug)]
+#[allow(dead_code)]
 enum CtxOption {
     IOThreads,
     MaxSockets,

libzmq/src/old.rs

@@ -54,6 +54,7 @@ fn recv(mut_sock_ptr: *mut c_void, msg: &mut Msg) -> Result<(), Error> {
     }
 }
 
+#[allow(dead_code)]
 pub(crate) enum OldSocketType {
     Router,
     Dealer,

libzmq/src/socket/gather.rs

@@ -314,6 +314,8 @@ mod test {
     use super::*;
     use crate::*;
 
+    use std::time::Duration;
+
     #[test]
     fn test_ser_de() {
         let config = GatherConfig::new();
@@ -323,6 +325,14 @@ mod test {
         assert_eq!(config, de);
     }
 
+    #[test]
+    fn test_issue_125() {
+        let gather = Gather::new().unwrap();
+        gather
+            .set_recv_timeout(Some(Duration::from_secs(3)))
+            .unwrap();
+    }
+
     #[test]
     fn test_gather() {
         let addr_a = InprocAddr::new_unique();