diff --git a/src/hb-common.cc b/src/hb-common.cc
index 26c8ad0..ea8ca2a 100644
--- a/src/hb-common.cc
+++ b/src/hb-common.cc
@@ -31,6 +31,10 @@
 
 #include <locale.h>
 
+#ifdef HAVE_XLOCALE_H
+#include <xlocale.h> // Needed on BSD/OS X for uselocale
+#endif
+
 #ifdef HB_NO_SETLOCALE
 #define setlocale(Category, Locale) "C"
 #endif
@@ -122,7 +126,7 @@
  * @tag: #hb_tag_t to convert
  * @buf: (out caller-allocates) (array fixed-size=4) (element-type uint8_t): Converted string
  *
- * Converts an #hb_tag_t to a string and returns it in @buf. 
+ * Converts an #hb_tag_t to a string and returns it in @buf.
  * Strings will be four characters long.
  *
  * Since: 0.9.5
@@ -151,13 +155,13 @@
  * @str: (array length=len) (element-type uint8_t): String to convert
  * @len: Length of @str, or -1 if it is %NULL-terminated
  *
- * Converts a string to an #hb_direction_t. 
+ * Converts a string to an #hb_direction_t.
  *
  * Matching is loose and applies only to the first letter. For
  * examples, "LTR" and "left-to-right" will both return #HB_DIRECTION_LTR.
  *
  * Unmatched strings will return #HB_DIRECTION_INVALID.
- * 
+ *
  * Return value: The #hb_direction_t matching @str
  *
  * Since: 0.9.2
@@ -1039,6 +1043,56 @@
   return false;
 }
 
+#if !defined(HARFBUZZ_NO_SETLOCALE) && defined(HAVE_NEWLOCALE) && defined(HAVE_USELOCALE)
+
+#ifdef WIN32
+using locale_t = _locale_t;
+#endif
+
+static inline void free_static_C_locale ();
+
+static struct hb_C_locale_lazy_loader_t : hb_lazy_loader_t<hb_remove_pointer<locale_t>,
+							     hb_C_locale_lazy_loader_t>
+{
+  static locale_t create ()
+  {
+    locale_t l = newlocale (LC_ALL_MASK, "C", NULL);
+    if (!l)
+      return l;
+
+    hb_atexit (free_static_C_locale);
+
+    return l;
+  }
+  static void destroy (locale_t l)
+  {
+    freelocale (l);
+  }
+  static locale_t get_null ()
+  {
+    return (locale_t) 0;
+  }
+} static_C_locale;
+
+static inline
+void free_static_C_locale ()
+{
+  static_C_locale.free_instance ();
+}
+
+static locale_t
+get_C_locale ()
+{
+  return static_C_locale.get_unconst ();
+}
+
+#else
+#ifdef WIN32
+#define locale_t void *
+#endif
+#define uselocale(Locale) ((locale_t) 0)
+#endif
+
 /**
  * hb_variation_to_string:
  * @variation: an #hb_variation_t to convert
@@ -1064,7 +1118,11 @@
   while (len && s[len - 1] == ' ')
     len--;
   s[len++] = '=';
+
+  locale_t oldlocale HB_UNUSED;
+  oldlocale = uselocale (get_C_locale ());
   len += hb_max (0, snprintf (s + len, ARRAY_LENGTH (s) - len, "%g", (double) variation->value));
+  (void) uselocale (oldlocale);
 
   assert (len < ARRAY_LENGTH (s));
   len = hb_min (len, size - 1);