win: fix some MinGW warnings

src/win/fs-fd-hash-inl.h

@@ -53,7 +53,8 @@ static struct uv__fd_hash_bucket_s uv__fd_hash[UV__FD_HASH_SIZE];
 
 
 INLINE static void uv__fd_hash_init(void) {
-  int i, err;
+  size_t i;
+  int err;
 
   err = uv_mutex_init(&uv__fd_hash_mutex);
   if (err) {

src/win/fs.c

@@ -737,7 +737,7 @@ void fs__close(uv_fs_t* req) {
 
 LONG fs__filemap_ex_filter(LONG excode, PEXCEPTION_POINTERS pep,
                            int* perror) {
-  if (excode != EXCEPTION_IN_PAGE_ERROR) {
+  if (excode != (LONG)EXCEPTION_IN_PAGE_ERROR) {
     return EXCEPTION_CONTINUE_SEARCH;
   }
 
@@ -816,10 +816,10 @@ void fs__read_filemap(uv_fs_t* req, struct uv__fd_info_s* fd_info) {
   for (index = 0;
        index < req->fs.info.nbufs && done_read < read_size;
        ++index) {
-    int err = 0;
     size_t this_read_size = MIN(req->fs.info.bufs[index].len,
                                 read_size - done_read);
 #ifdef _MSC_VER
+    int err = 0;
     __try {
 #endif
       memcpy(req->fs.info.bufs[index].base,
@@ -938,7 +938,7 @@ void fs__write_filemap(uv_fs_t* req, HANDLE file,
     (UV_FS_O_RDONLY | UV_FS_O_WRONLY | UV_FS_O_RDWR);
   size_t write_size, done_write;
   unsigned int index;
-  LARGE_INTEGER zero, pos, end_pos;
+  LARGE_INTEGER pos, end_pos;
   size_t view_offset;
   LARGE_INTEGER view_base;
   void* view;
@@ -963,7 +963,6 @@ void fs__write_filemap(uv_fs_t* req, HANDLE file,
     return;
   }
 
-  zero.QuadPart = 0;
   if (force_append) {
     pos = fd_info->size;
   } else if (req->fs.info.offset == -1) {
@@ -1014,8 +1013,8 @@ void fs__write_filemap(uv_fs_t* req, HANDLE file,
 
   done_write = 0;
   for (index = 0; index < req->fs.info.nbufs; ++index) {
-    int err = 0;
 #ifdef _MSC_VER
+    int err = 0;
     __try {
 #endif
       memcpy((char*)view + view_offset + done_write,
@@ -1407,7 +1406,7 @@ void fs__scandir(uv_fs_t* req) {
   /* If the handle is not a directory, we'll get STATUS_INVALID_PARAMETER.
    * This should be reported back as UV_ENOTDIR.
    */
-  if (status == STATUS_INVALID_PARAMETER)
+  if (status == (NTSTATUS)STATUS_INVALID_PARAMETER)
     goto not_a_directory_error;
 
   while (NT_SUCCESS(status)) {

src/win/tty.c

@@ -2413,6 +2413,7 @@ static DWORD WINAPI uv__tty_console_resize_watcher_thread(void* param) {
     uv__tty_console_signal_resize();
     ResetEvent(uv__tty_console_resized);
   }
+  return 0;
 }
 
 static void uv__tty_console_signal_resize(void) {

src/win/util.c

@@ -30,12 +30,14 @@
 #include "uv.h"
 #include "internal.h"
 
+/* clang-format off */
 #include <winsock2.h>
 #include <winperf.h>
 #include <iphlpapi.h>
 #include <psapi.h>
 #include <tlhelp32.h>
 #include <windows.h>
+/* clang-format on */
 #include <userenv.h>
 #include <math.h>
 
@@ -1806,7 +1808,9 @@ int uv_os_uname(uv_utsname_t* buffer) {
     pRtlGetVersion(&os_info);
   } else {
     /* Silence GetVersionEx() deprecation warning. */
+    #ifdef _MSC_VER
     #pragma warning(suppress : 4996)
+    #endif
     if (GetVersionExW(&os_info) == 0) {
       r = uv_translate_sys_error(GetLastError());
       goto error;
@@ -1873,7 +1877,7 @@ int uv_os_uname(uv_utsname_t* buffer) {
                "MINGW32_NT-%u.%u",
                (unsigned int) os_info.dwMajorVersion,
                (unsigned int) os_info.dwMinorVersion);
-  assert(r < sizeof(buffer->sysname));
+  assert((size_t)r < sizeof(buffer->sysname));
 #else
   uv__strscpy(buffer->sysname, "Windows_NT", sizeof(buffer->sysname));
 #endif
@@ -1885,7 +1889,7 @@ int uv_os_uname(uv_utsname_t* buffer) {
                (unsigned int) os_info.dwMajorVersion,
                (unsigned int) os_info.dwMinorVersion,
                (unsigned int) os_info.dwBuildNumber);
-  assert(r < sizeof(buffer->release));
+  assert((size_t)r < sizeof(buffer->release));
 
   /* Populate the machine field. */
   GetSystemInfo(&system_info);