Mark certain mutex lock macros as private

mbtowc() mblen(), and wctomb() should not be directly used by XS
writers; instead use the POSIX versions.  Don't encourage the direct use
by having public macros to aid in their use.

ext/POSIX/POSIX.xs

@@ -3163,9 +3163,9 @@ mblen(s, n = ~0)
             memzero(&PL_mbrlen_ps, sizeof(PL_mbrlen_ps));
             RETVAL = 0;
 #else
-            MBLEN_LOCK;
+            MBLEN_LOCK_;
             RETVAL = mblen(NULL, 0);
-            MBLEN_UNLOCK;
+            MBLEN_UNLOCK_;
 #endif
         }
         else {  /* Not resetting state */
@@ -3185,9 +3185,9 @@ mblen(s, n = ~0)
 #else
                 /* Locking prevents races, but locales can be switched out
                  * without locking, so this isn't a cure all */
-                MBLEN_LOCK;
+                MBLEN_LOCK_;
                 RETVAL = mblen(string, len);
-                MBLEN_UNLOCK;
+                MBLEN_UNLOCK_;
 #endif
             }
         }
@@ -3250,9 +3250,9 @@ wctomb(s, wchar)
              * But probably memzero would too */
             RETVAL = wcrtomb(NULL, L'\0', &PL_wcrtomb_ps);
 #else
-            WCTOMB_LOCK;
+            WCTOMB_LOCK_;
             RETVAL = wctomb(NULL, L'\0');
-            WCTOMB_UNLOCK;
+            WCTOMB_UNLOCK_;
 #endif
         }
         else {  /* Not resetting state */
@@ -3262,9 +3262,9 @@ wctomb(s, wchar)
 #else
             /* Locking prevents races, but locales can be switched out without
              * locking, so this isn't a cure all */
-            WCTOMB_LOCK;
+            WCTOMB_LOCK_;
             RETVAL = wctomb(buffer, wchar);
-            WCTOMB_UNLOCK;
+            WCTOMB_UNLOCK_;
 #endif
             if (RETVAL >= 0) {
                 sv_setpvn_mg(s, buffer, RETVAL);

locale.c

@@ -2883,10 +2883,10 @@ Perl_mbtowc_(pTHX_ const wchar_t * pwc, const char * s, const Size_t len)
 
 #  else
 
-        MBTOWC_LOCK;
+        MBTOWC_LOCK_;
         SETERRNO(0, 0);
         retval = mbtowc(NULL, NULL, 0);
-        MBTOWC_UNLOCK;
+        MBTOWC_UNLOCK_;
         return retval;
 
 #  endif
@@ -2902,10 +2902,10 @@ Perl_mbtowc_(pTHX_ const wchar_t * pwc, const char * s, const Size_t len)
 
     /* Locking prevents races, but locales can be switched out without locking,
      * so this isn't a cure all */
-    MBTOWC_LOCK;
+    MBTOWC_LOCK_;
     SETERRNO(0, 0);
     retval = mbtowc((wchar_t *) pwc, s, len);
-    MBTOWC_UNLOCK;
+    MBTOWC_UNLOCK_;
 
 #  endif
 

perl.h

@@ -6676,14 +6676,14 @@ the plain locale pragma without a parameter (S<C<use locale>>) is in effect.
 #  define LOCALE_READ_UNLOCK        NOOP
 #  define MBLEN_LOCK                NOOP
 #  define MBLEN_UNLOCK              NOOP
-#  define MBTOWC_LOCK               NOOP
-#  define MBTOWC_UNLOCK             NOOP
+#  define MBTOWC_LOCK_              NOOP
+#  define MBTOWC_UNLOCK_            NOOP
 #  define NL_LANGINFO_LOCK          NOOP
 #  define NL_LANGINFO_UNLOCK        NOOP
 #  define SETLOCALE_LOCK            NOOP
 #  define SETLOCALE_UNLOCK          NOOP
-#  define WCTOMB_LOCK               NOOP
-#  define WCTOMB_UNLOCK             NOOP
+#  define WCTOMB_LOCK_              NOOP
+#  define WCTOMB_UNLOCK_            NOOP
 #else
 
    /* Here, we will need critical sections in locale handling, because one or
@@ -6743,16 +6743,16 @@ the plain locale pragma without a parameter (S<C<use locale>>) is in effect.
 #    define NL_LANGINFO_UNLOCK LOCALE_UNLOCK_
 #  endif
 #  if defined(HAS_MBLEN) && ! defined(HAS_MBRLEN)
-#    define MBLEN_LOCK   LOCALE_LOCK_
-#    define MBLEN_UNLOCK LOCALE_UNLOCK_
+#    define MBLEN_LOCK_   LOCALE_LOCK_
+#    define MBLEN_UNLOCK_ LOCALE_UNLOCK_
 #  endif
 #  if defined(HAS_MBTOWC) && ! defined(HAS_MBRTOWC)
-#    define MBTOWC_LOCK   LOCALE_LOCK_
-#    define MBTOWC_UNLOCK LOCALE_UNLOCK_
+#    define MBTOWC_LOCK_   LOCALE_LOCK_
+#    define MBTOWC_UNLOCK_ LOCALE_UNLOCK_
 #  endif
 #  if defined(HAS_WCTOMB) && ! defined(HAS_WCRTOMB)
-#    define WCTOMB_LOCK   LOCALE_LOCK_
-#    define WCTOMB_UNLOCK LOCALE_UNLOCK_
+#    define WCTOMB_LOCK_   LOCALE_LOCK_
+#    define WCTOMB_UNLOCK_ LOCALE_UNLOCK_
 #  endif
 #  if defined(USE_THREAD_SAFE_LOCALE)
      /* On locale thread-safe systems, we don't need these workarounds */