diff --git a/src/host/buffered_io.c b/src/host/buffered_io.c
index 160bbccf..018402be 100644
--- a/src/host/buffered_io.c
+++ b/src/host/buffered_io.c
@@ -16,7 +16,7 @@ void buffer_init(Buffer* b)
 	b->data = NULL;
 }
 
-void buffer_destroy(Buffer* b) 
+void buffer_destroy(Buffer* b)
 {
 	free(b->data);
 	b->capacity = 0;
@@ -53,12 +53,13 @@ void buffer_puts(Buffer* b, const void* ptr, size_t len)
 	b->length += len;
 }
 
-void buffer_printf(Buffer* b, const char *fmt, ...) 
+void buffer_printf(Buffer* b, const char *fmt, ...)
 {
 	char text[2048];
+	int len;
 	va_list args;
 	va_start(args, fmt);
-	int len = vsnprintf(text, sizeof(text) - 1, fmt, args);
+	len = vsnprintf(text, sizeof(text) - 1, fmt, args);
 	va_end(args);
 	buffer_puts(b, text, len);
 }
diff --git a/src/host/os_chdir.c b/src/host/os_chdir.c
index 28aa0fcd..b51292af 100644
--- a/src/host/os_chdir.c
+++ b/src/host/os_chdir.c
@@ -11,8 +11,6 @@ int do_chdir(lua_State* L, const char* path)
 {
 	int z;
 
-	(void)(L);  /* warning: unused parameter */
-
 #if PLATFORM_WINDOWS
 	wchar_t wide_buffer[PATH_MAX];
 	if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_buffer, PATH_MAX) == 0)
@@ -23,6 +21,8 @@ int do_chdir(lua_State* L, const char* path)
 
 	z = SetCurrentDirectoryW(wide_buffer);
 #else
+	(void)(L);  /* warning: unused parameter */
+
 	z = !chdir(path);
 #endif
 
diff --git a/src/host/os_getversion.c b/src/host/os_getversion.c
index 970ff237..40b0c83c 100644
--- a/src/host/os_getversion.c
+++ b/src/host/os_getversion.c
@@ -67,7 +67,7 @@ int getKernelVersion(struct OsVersionInfo* info)
 		{
 			void* fixedInfoPtr;
 			UINT fixedInfoSize;
-			if (VerQueryValueA(data, "\\", &fixedInfoPtr, &fixedInfoSize)) 
+			if (VerQueryValueA(data, "\\", &fixedInfoPtr, &fixedInfoSize))
 			{
 				VS_FIXEDFILEINFO* fileInfo = (VS_FIXEDFILEINFO*)fixedInfoPtr;
 				info->majorversion = HIWORD(fileInfo->dwProductVersionMS);
@@ -82,10 +82,10 @@ int getKernelVersion(struct OsVersionInfo* info)
 
 int getversion(struct OsVersionInfo* info)
 {
+	HKEY key;
 	info->description = "Windows";
 
 	// First get a friendly product name from the registry.
-	HKEY key;
 	if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, "Software\\Microsoft\\Windows NT\\CurrentVersion", 0, KEY_READ, &key) == ERROR_SUCCESS)
 	{
 		char value[512];
diff --git a/src/host/os_isfile.c b/src/host/os_isfile.c
index 2bad6f04..c2a10768 100644
--- a/src/host/os_isfile.c
+++ b/src/host/os_isfile.c
@@ -18,10 +18,9 @@ int os_isfile(lua_State* L)
 
 int do_isfile(lua_State* L, const char* filename)
 {
-	(void)(L);  /* warning: unused parameter */
-
 #if PLATFORM_WINDOWS
 	wchar_t wide_path[PATH_MAX];
+	DWORD attrib;
 
 	if (MultiByteToWideChar(CP_UTF8, 0, filename, -1, wide_path, PATH_MAX) == 0)
 	{
@@ -29,13 +28,16 @@ int do_isfile(lua_State* L, const char* filename)
 		return lua_error(L);
 	}
 
-	DWORD attrib = GetFileAttributesW(wide_path);
+	attrib = GetFileAttributesW(wide_path);
 	if (attrib != INVALID_FILE_ATTRIBUTES)
 	{
 		return (attrib & FILE_ATTRIBUTE_DIRECTORY) == 0;
 	}
 #else
 	struct stat buf;
+
+	(void)(L);  /* warning: unused parameter */
+
 	if (stat(filename, &buf) == 0)
 	{
 		return ((buf.st_mode & S_IFDIR) == 0);
diff --git a/src/host/os_islink.c b/src/host/os_islink.c
index 1c2dee91..4ce0902d 100644
--- a/src/host/os_islink.c
+++ b/src/host/os_islink.c
@@ -15,13 +15,14 @@ int os_islink(lua_State* L)
 #if PLATFORM_WINDOWS
 	{
 		wchar_t wide_path[PATH_MAX];
+		DWORD attr;
 		if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_path, PATH_MAX) == 0)
 		{
 			lua_pushstring(L, "unable to encode path");
 			return lua_error(L);
 		}
 
-		DWORD attr = GetFileAttributesW(wide_path);
+		attr = GetFileAttributesW(wide_path);
 		if (attr != INVALID_FILE_ATTRIBUTES) {
 			lua_pushboolean(L, (attr & FILE_ATTRIBUTE_REPARSE_POINT) != 0);
 			return 1;
diff --git a/src/host/os_match.c b/src/host/os_match.c
index 2a25df68..a60e64d7 100644
--- a/src/host/os_match.c
+++ b/src/host/os_match.c
@@ -21,6 +21,7 @@ typedef struct struct_MatchInfo
 int os_matchstart(lua_State* L)
 {
 	const char* mask = luaL_checkstring(L, 1);
+	MatchInfo* m;
 
 	wchar_t wide_mask[PATH_MAX];
 	if (MultiByteToWideChar(CP_UTF8, 0, mask, -1, wide_mask, PATH_MAX) == 0)
@@ -29,7 +30,7 @@ int os_matchstart(lua_State* L)
 		return lua_error(L);
 	}
 
-	MatchInfo* m = (MatchInfo*)malloc(sizeof(MatchInfo));
+	m = (MatchInfo*)malloc(sizeof(MatchInfo));
 
 	m->handle = FindFirstFileW(wide_mask, &m->entry);
 	m->is_first = 1;