diff --git a/embedvar.h b/embedvar.h
index 8c6584722f17..de295d2da250 100644
--- a/embedvar.h
+++ b/embedvar.h
@@ -87,6 +87,7 @@
 #define PL_cop_seqmax		(vTHX->Icop_seqmax)
 #define PL_ctype_name		(vTHX->Ictype_name)
 #define PL_cur_LC_ALL		(vTHX->Icur_LC_ALL)
+#define PL_cur_locale_obj	(vTHX->Icur_locale_obj)
 #define PL_curcop		(vTHX->Icurcop)
 #define PL_curcopdb		(vTHX->Icurcopdb)
 #define PL_curlocales		(vTHX->Icurlocales)
diff --git a/intrpvar.h b/intrpvar.h
index 6a3b752a2450..bdc7e83173b8 100644
--- a/intrpvar.h
+++ b/intrpvar.h
@@ -739,6 +739,9 @@ PERLVAR(I, constpadix,	PADOFFSET)	/* lowest unused for constants */
 
 PERLVAR(I, padix_floor,	PADOFFSET)	/* how low may inner block reset padix */
 
+#if defined(USE_POSIX_2008_LOCALE) && defined(MULTIPLICITY)
+PERLVARI(I, cur_locale_obj, locale_t, NULL)
+#endif
 #ifdef USE_PL_CURLOCALES
 
 /* This is the most number of categories we've encountered so far on any
diff --git a/locale.c b/locale.c
index 5e909f17da41..5083c3b98a09 100644
--- a/locale.c
+++ b/locale.c
@@ -1372,6 +1372,10 @@ S_emulate_setlocale_i(pTHX_
     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
              "(%" LINE_Tf "): emulate_setlocale_i now using %p\n", line, new_obj));
 
+#ifdef MULTIPLICITY
+    PL_cur_locale_obj = new_obj;
+#endif
+
     /* We are done, except for updating our records (if the system doesn't keep
      * them) and in the case of locale "", we don't actually know what the
      * locale that got switched to is, as it came from the environment.  So
@@ -6726,31 +6730,28 @@ S_my_setlocale_debug_string_i(pTHX_
 void
 Perl_thread_locale_init(pTHX)
 {
-    /* Called from a thread on startup*/
 
 #ifdef USE_THREAD_SAFE_LOCALE
+#  ifdef USE_POSIX_2008_LOCALE
+
+    /* Called from a thread on startup.
+     *
+     * The operations here have to be done from within the calling thread, as
+     * they affect libc's knowledge of the thread; libc has no knowledge of
+     * aTHX */
 
      DEBUG_L(PerlIO_printf(Perl_debug_log,
                            "new thread, initial locale is %s;"
                            " calling setlocale(LC_ALL, \"C\")\n",
                            get_LC_ALL_display()));
-#  ifdef WIN32
 
-    /* On Windows, make sure new thread has per-thread locales enabled */
-    _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
-
-#  endif
-#  if defined(LC_ALL)
+    uselocale(PL_C_locale_obj);
 
-    /* This thread starts off in the C locale.  Use the full Perl_setlocale()
-     * to make sure no ill-advised shortcuts get taken on this new thread, */
-    Perl_setlocale(LC_ALL, "C");
+#  elif defined(WIN32)
 
-#  else
-
-    for (unsigned i = 0; i < NOMINAL_LC_ALL_INDEX; i++) {
-        Perl_setlocale(categories[i], "C");
-    }
+    /* On Windows, make sure new thread has per-thread locales enabled */
+    _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
+    void_setlocale_c(LC_ALL, "C");
 
 #  endif
 #endif
@@ -6760,20 +6761,34 @@ Perl_thread_locale_init(pTHX)
 void
 Perl_thread_locale_term(pTHX)
 {
-    /* Called from a thread as it gets ready to terminate */
+    /* Called from a thread as it gets ready to terminate.
+     *
+     * The operations here have to be done from within the calling thread, as
+     * they affect libc's knowledge of the thread; libc has no knowledge of
+     * aTHX */
 
 #ifdef USE_POSIX_2008_LOCALE
 
     /* C starts the new thread in the global C locale.  If we are thread-safe,
      * we want to not be in the global locale */
 
-    {   /* Free up */
-        locale_t cur_obj = uselocale(LC_GLOBAL_LOCALE);
-        if (cur_obj != LC_GLOBAL_LOCALE && cur_obj != PL_C_locale_obj) {
-            freelocale(cur_obj);
-        }
+    /* Free up */
+    locale_t actual_obj   = uselocale(LC_GLOBAL_LOCALE);
+    if (actual_obj != LC_GLOBAL_LOCALE && actual_obj != PL_C_locale_obj) {
+        freelocale(actual_obj);
     }
 
+    /* Prevent leaks even if something has gone wrong */
+    locale_t expected_obj = PL_cur_locale_obj;
+    if (UNLIKELY(   expected_obj != actual_obj
+                 && expected_obj != LC_GLOBAL_LOCALE
+                 && expected_obj != PL_C_locale_obj))
+    {
+        freelocale(expected_obj);
+    }
+
+    PL_cur_locale_obj = LC_GLOBAL_LOCALE;
+
 #endif
 
 }
diff --git a/makedef.pl b/makedef.pl
index ca30c43d646f..acea937ebcca 100644
--- a/makedef.pl
+++ b/makedef.pl
@@ -386,6 +386,7 @@ sub readvar {
     ++$skip{$_} foreach qw(
                     PL_keyword_plugin_mutex
 		    PL_check_mutex
+                    PL_cur_locale_obj
 		    PL_op_mutex
 		    PL_regex_pad
 		    PL_regex_padav
diff --git a/perl.c b/perl.c
index 0a3ec39811ce..417381683c1e 100644
--- a/perl.c
+++ b/perl.c
@@ -1129,15 +1129,17 @@ perl_destruct(pTHXx)
     {
         /* This also makes sure we aren't using a locale object that gets freed
          * below */
-        const locale_t old_locale = uselocale(LC_GLOBAL_LOCALE);
-        if (   old_locale != LC_GLOBAL_LOCALE
-#  ifdef USE_POSIX_2008_LOCALE
-            && old_locale != PL_C_locale_obj
-#  endif
+        if (   PL_cur_locale_obj != NULL
+            && PL_cur_locale_obj != LC_GLOBAL_LOCALE
+            && PL_cur_locale_obj != PL_C_locale_obj
         ) {
-            DEBUG_Lv(PerlIO_printf(Perl_debug_log,
-                     "%s:%d: Freeing %p\n", __FILE__, __LINE__, old_locale));
-            freelocale(old_locale);
+            locale_t cur_locale = uselocale((locale_t) 0);
+            if (cur_locale == PL_cur_locale_obj) {
+                uselocale(LC_GLOBAL_LOCALE);
+            }
+
+            freelocale(PL_cur_locale_obj);
+            PL_cur_locale_obj = NULL;
         }
     }
 
diff --git a/sv.c b/sv.c
index bc5f95143b2d..99b71c65ab1c 100644
--- a/sv.c
+++ b/sv.c
@@ -15939,6 +15939,7 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
 #endif /* !USE_LOCALE_NUMERIC */
 #if defined(USE_POSIX_2008_LOCALE)
     PL_scratch_locale_obj = NULL;
+    PL_cur_locale_obj = PL_C_locale_obj;
 #endif
 
 #ifdef HAS_MBRLEN