diff --git a/wpiutil/src/main/native/cpp/json_binary_writer.cpp b/wpiutil/src/main/native/cpp/json_binary_writer.cpp
index 75c39aa763..2c0bbeea70 100644
--- a/wpiutil/src/main/native/cpp/json_binary_writer.cpp
+++ b/wpiutil/src/main/native/cpp/json_binary_writer.cpp
@@ -956,7 +956,7 @@ json::binary_writer::CharType json::binary_writer::ubjson_prefix(const json& j)
 
         case value_t::number_unsigned:
         {
-            if (j.m_value.number_unsigned <= (std::numeric_limits<int8_t>::max)())
+            if (j.m_value.number_unsigned <= static_cast<uint64_t>((std::numeric_limits<int8_t>::max)()))
             {
                 return 'i';
             }
@@ -964,11 +964,11 @@ json::binary_writer::CharType json::binary_writer::ubjson_prefix(const json& j)
             {
                 return 'U';
             }
-            else if (j.m_value.number_unsigned <= (std::numeric_limits<int16_t>::max)())
+            else if (j.m_value.number_unsigned <= static_cast<uint64_t>((std::numeric_limits<int16_t>::max)()))
             {
                 return 'I';
             }
-            else if (j.m_value.number_unsigned <= (std::numeric_limits<int32_t>::max)())
+            else if (j.m_value.number_unsigned <= static_cast<uint64_t>((std::numeric_limits<int32_t>::max)()))
             {
                 return 'l';
             }
diff --git a/wpiutil/src/main/native/libuv/include/uv/unix.h b/wpiutil/src/main/native/libuv/include/uv/unix.h
index 5dae6ddfa2..34978e3388 100644
--- a/wpiutil/src/main/native/libuv/include/uv/unix.h
+++ b/wpiutil/src/main/native/libuv/include/uv/unix.h
@@ -191,7 +191,7 @@ typedef struct {
   int backend_fd;                                                             \
   void* pending_queue[2];                                                     \
   void* watcher_queue[2];                                                     \
-  uv__io_t** watchers;                                                        \
+  void** watchers;                                                            \
   unsigned int nwatchers;                                                     \
   unsigned int nfds;                                                          \
   void* wq[2];                                                                \
diff --git a/wpiutil/src/main/native/libuv/src/unix/core.cpp b/wpiutil/src/main/native/libuv/src/unix/core.cpp
index df36747844..137a9bf0d8 100644
--- a/wpiutil/src/main/native/libuv/src/unix/core.cpp
+++ b/wpiutil/src/main/native/libuv/src/unix/core.cpp
@@ -794,7 +794,7 @@ static unsigned int next_power_of_two(unsigned int val) {
 }
 
 static void maybe_resize(uv_loop_t* loop, unsigned int len) {
-  uv__io_t** watchers;
+  void** watchers;
   void* fake_watcher_list;
   void* fake_watcher_count;
   unsigned int nwatchers;
@@ -813,15 +813,15 @@ static void maybe_resize(uv_loop_t* loop, unsigned int len) {
   }
 
   nwatchers = next_power_of_two(len + 2) - 2;
-  watchers = (uv__io_t**)
+  watchers = (void**)
       uv__realloc(loop->watchers, (nwatchers + 2) * sizeof(loop->watchers[0]));
 
   if (watchers == NULL)
     abort();
   for (i = loop->nwatchers; i < nwatchers; i++)
     watchers[i] = NULL;
-  watchers[nwatchers] = (uv__io_t*)fake_watcher_list;
-  watchers[nwatchers + 1] = (uv__io_t*)fake_watcher_count;
+  watchers[nwatchers] = fake_watcher_list;
+  watchers[nwatchers + 1] = fake_watcher_count;
 
   loop->watchers = watchers;
   loop->nwatchers = nwatchers;
diff --git a/wpiutil/src/main/native/libuv/src/unix/kqueue.cpp b/wpiutil/src/main/native/libuv/src/unix/kqueue.cpp
index 6e2b2bb9fd..57d96b74bf 100644
--- a/wpiutil/src/main/native/libuv/src/unix/kqueue.cpp
+++ b/wpiutil/src/main/native/libuv/src/unix/kqueue.cpp
@@ -258,7 +258,7 @@ void uv__io_poll(uv_loop_t* loop, int timeout) {
       /* Skip invalidated events, see uv__platform_invalidate_fd */
       if (fd == -1)
         continue;
-      w = loop->watchers[fd];
+      w = (uv__io_t*)loop->watchers[fd];
 
       if (w == NULL) {
         /* File descriptor that we've stopped watching, disarm it.
diff --git a/wpiutil/src/main/native/libuv/src/unix/linux-core.cpp b/wpiutil/src/main/native/libuv/src/unix/linux-core.cpp
index 3bf8beb559..375b93a76c 100644
--- a/wpiutil/src/main/native/libuv/src/unix/linux-core.cpp
+++ b/wpiutil/src/main/native/libuv/src/unix/linux-core.cpp
@@ -344,8 +344,8 @@ void uv__io_poll(uv_loop_t* loop, int timeout) {
     nevents = 0;
 
     assert(loop->watchers != NULL);
-    loop->watchers[loop->nwatchers] = (uv__io_t*) events;
-    loop->watchers[loop->nwatchers + 1] = (uv__io_t*) (uintptr_t) nfds;
+    loop->watchers[loop->nwatchers] = events;
+    loop->watchers[loop->nwatchers + 1] = (void*) (uintptr_t) nfds;
     for (i = 0; i < nfds; i++) {
       pe = events + i;
       fd = pe->data;
@@ -357,7 +357,7 @@ void uv__io_poll(uv_loop_t* loop, int timeout) {
       assert(fd >= 0);
       assert((unsigned) fd < loop->nwatchers);
 
-      w = loop->watchers[fd];
+      w = (uv__io_t*)loop->watchers[fd];
 
       if (w == NULL) {
         /* File descriptor that we've stopped watching, disarm it.
diff --git a/wpiutil/src/main/native/libuv/src/unix/loop.cpp b/wpiutil/src/main/native/libuv/src/unix/loop.cpp
index f990403d40..1458f6882d 100644
--- a/wpiutil/src/main/native/libuv/src/unix/loop.cpp
+++ b/wpiutil/src/main/native/libuv/src/unix/loop.cpp
@@ -129,7 +129,7 @@ int uv_loop_fork(uv_loop_t* loop) {
 
   /* Rearm all the watchers that aren't re-queued by the above. */
   for (i = 0; i < loop->nwatchers; i++) {
-    w = loop->watchers[i];
+    w = (uv__io_t*)loop->watchers[i];
     if (w == NULL)
       continue;