Make host_args.c obey REBCHR sizing

I'm not exactly sure how the Windows build worked when the argument
processing wasn't obeying the rules for REBCHR being a wide character.
This makes sure the comparisons being done are on the wchar_t type
in the Win32 build.

As a reminder: I think REBCHR is indicative of a design problem, so I
don't feel great about adding another OS_STRxxx wrapper.  But at least
it is "quarantined".

src/core/n-strings.c

@@ -946,6 +946,22 @@ static struct digest {
 }
 
 
+/***********************************************************************
+**
+*/	int OS_STRNCMP_(const REBCHR *lhs, const REBCHR *rhs, size_t max)
+/*
+**		Debug-only REBCHR-checked substitute for OS_STRNCMP macro
+**
+***********************************************************************/
+{
+#ifdef OS_WIDE_CHAR
+	return wcsncmp(cast(const wchar_t*, lhs), cast(const wchar_t*, rhs), max);
+#else
+	return strncmp(cast(const char*, lhs), cast (const char*, rhs), max);
+#endif
+}
+
+
 /***********************************************************************
 **
 */	size_t OS_STRLEN_(const REBCHR *str)
@@ -971,7 +987,7 @@ static struct digest {
 ***********************************************************************/
 {
 #ifdef OS_WIDE_CHAR
-	return wcschr(cast(const wchar_t*, str), ch);
+	return cast(REBCHR*, wcschr(cast(const wchar_t*, str), ch));
 #else
 	// We have to m_cast because C++ actually has a separate overload of
 	// strchr which will return a const pointer if the in pointer was const

src/os/host-args.c

@@ -47,23 +47,23 @@
 
 // REBOL Option --Words:
 
-const struct {const char *word; const int flag;} arg_words[] = {
+const struct {REBCHR *word; const int flag;} arg_words[] = {
 	// Keep in Alpha order!
-	{"args",		RO_ARGS | RO_EXT},
-	{"boot",		RO_BOOT | RO_EXT},
-	{"cgi",			RO_CGI | RO_QUIET},
-	{"debug",		RO_DEBUG | RO_EXT},
-	{"do",			RO_DO | RO_EXT},
-	{"halt",		RO_HALT},
-	{"help",		RO_HELP},
-	{"import",		RO_IMPORT | RO_EXT},
-	{"quiet",		RO_QUIET},
-	{"script",		RO_SCRIPT | RO_EXT},
-	{"secure",		RO_SECURE | RO_EXT},
-	{"trace",		RO_TRACE},
-	{"verbose",		RO_VERBOSE},
-	{"version",		RO_VERSION | RO_EXT},
-	{"",			0},
+	{OS_STR_LIT("args"),		RO_ARGS | RO_EXT},
+	{OS_STR_LIT("boot"),		RO_BOOT | RO_EXT},
+	{OS_STR_LIT("cgi"),			RO_CGI | RO_QUIET},
+	{OS_STR_LIT("debug"),		RO_DEBUG | RO_EXT},
+	{OS_STR_LIT("do"),			RO_DO | RO_EXT},
+	{OS_STR_LIT("halt"),		RO_HALT},
+	{OS_STR_LIT("help"),		RO_HELP},
+	{OS_STR_LIT("import"),		RO_IMPORT | RO_EXT},
+	{OS_STR_LIT("quiet"),		RO_QUIET},
+	{OS_STR_LIT("script"),		RO_SCRIPT | RO_EXT},
+	{OS_STR_LIT("secure"),		RO_SECURE | RO_EXT},
+	{OS_STR_LIT("trace"),		RO_TRACE},
+	{OS_STR_LIT("verbose"),		RO_VERBOSE},
+	{OS_STR_LIT("version"),		RO_VERSION | RO_EXT},
+	{OS_STR_LIT(""),			0},
 };
 
 // REBOL Option -Characters (in alpha sorted order):
@@ -100,15 +100,15 @@ const struct arg_chr arg_chars2[] = {
 {
 	int n;
 	int i;
-	char buf[16];
+	REBCHR buf[16];
 
 	// Some shells will pass us the line terminator. Ignore it.
 	if (word[0] == '\r' || word[0] == '\n') return RO_IGNORE;
 
 	OS_STRNCPY(buf, word, 15);
 
 	for (i = 0; arg_words[i].flag; i++) {
-		n = strncmp(buf, arg_words[i].word, 15); // correct (bytes)
+		n = OS_STRNCMP(buf, arg_words[i].word, 15);
 		if (n < 0) break;
 		if (n == 0) return arg_words[i].flag;
 	}