diff --git a/server/named_pipe.c b/server/named_pipe.c
index cd9d0d6b0f0..b22dfb1524f 100644
--- a/server/named_pipe.c
+++ b/server/named_pipe.c
@@ -712,7 +712,7 @@ DECL_HANDLER(wait_named_pipe)
     }
     else
     {
-        unsigned int timeout;
+        int timeout;
         if (req->timeout == NMPWAIT_USE_DEFAULT_WAIT)
             timeout = pipe->timeout;
         else
diff --git a/server/registry.c b/server/registry.c
index 4b01b525c5a..b34301d5e5e 100644
--- a/server/registry.c
+++ b/server/registry.c
@@ -879,7 +879,7 @@ static void set_value( struct key *key, WCHAR *name, int type, const void *data,
 }
 
 /* get a key value */
-static void get_value( struct key *key, const WCHAR *name, int *type, int *len )
+static void get_value( struct key *key, const WCHAR *name, int *type, unsigned int *len )
 {
     struct key_value *value;
     int index;
diff --git a/server/request.c b/server/request.c
index 1fd19c17fb3..6aa00729a89 100644
--- a/server/request.c
+++ b/server/request.c
@@ -488,7 +488,7 @@ static void master_socket_poll_event( struct fd *fd, int event )
     else if (event & POLLIN)
     {
         struct sockaddr_un dummy;
-        int len = sizeof(dummy);
+        unsigned int len = sizeof(dummy);
         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
         if (client == -1) return;
         if (sock->timeout)
diff --git a/server/sock.c b/server/sock.c
index 4f164a750c6..0a9b4225d2d 100644
--- a/server/sock.c
+++ b/server/sock.c
@@ -623,7 +623,6 @@ static struct sock *accept_socket( obj_handle_t handle )
     struct sock *sock;
     int	acceptfd;
     struct sockaddr	saddr;
-    int			slen;
 
     sock=(struct sock*)get_handle_obj(current->process,handle,
                                       GENERIC_READ|GENERIC_WRITE|SYNCHRONIZE,&sock_ops);
@@ -642,7 +641,7 @@ static struct sock *accept_socket( obj_handle_t handle )
          * or that accept() is allowed on it. In those cases we will get -1/errno
          * return.
          */
-        slen = sizeof(saddr);
+        unsigned int slen = sizeof(saddr);
         acceptfd = accept( get_unix_fd(sock->fd), &saddr, &slen);
         if (acceptfd==-1)
         {
diff --git a/server/thread.c b/server/thread.c
index b035bb97b5a..e314314cce6 100644
--- a/server/thread.c
+++ b/server/thread.c
@@ -734,8 +734,8 @@ static void get_selector_entry( struct thread *thread, int entry,
     {
         unsigned char flags_buf[4];
         int *addr = (int *)thread->process->ldt_copy + entry;
-        if (read_thread_int( thread, addr, base ) == -1) goto done;
-        if (read_thread_int( thread, addr + 8192, limit ) == -1) goto done;
+        if (read_thread_int( thread, addr, (int *)base ) == -1) goto done;
+        if (read_thread_int( thread, addr + 8192, (int *)limit ) == -1) goto done;
         addr = (int *)thread->process->ldt_copy + 2*8192 + (entry >> 2);
         if (read_thread_int( thread, addr, (int *)flags_buf ) == -1) goto done;
         *flags = flags_buf[entry & 3];