diff --git a/libstdc++-v3/include/bits/regex.h b/libstdc++-v3/include/bits/regex.h
index 4244f2e..30189e3 100644
--- a/libstdc++-v3/include/bits/regex.h
+++ b/libstdc++-v3/include/bits/regex.h
@@ -97,14 +97,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     private:
       struct _RegexMask
 	{
-	  typedef typename std::ctype<char_type>::mask _BaseType;
+	  typedef std::ctype_base::mask _BaseType;
 	  _BaseType _M_base;
 	  unsigned char _M_extended;
 	  static constexpr unsigned char _S_under = 1 << 0;
-	  // FIXME: _S_blank should be removed in the future,
-	  // when locale's complete.
-	  static constexpr unsigned char _S_blank = 1 << 1;
-	  static constexpr unsigned char _S_valid_mask = 0x3;
+	  static constexpr unsigned char _S_valid_mask = 0x1;
 
 	  constexpr _RegexMask(_BaseType __base = 0,
 			       unsigned char __extended = 0)
diff --git a/libstdc++-v3/include/bits/regex.tcc b/libstdc++-v3/include/bits/regex.tcc
index 3322379..94cbbfa 100644
--- a/libstdc++-v3/include/bits/regex.tcc
+++ b/libstdc++-v3/include/bits/regex.tcc
@@ -335,7 +335,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	{"s", ctype_base::space},
 	{"alnum", ctype_base::alnum},
 	{"alpha", ctype_base::alpha},
-	{"blank", {0, _RegexMask::_S_blank}},
+	{"blank", ctype_base::blank},
 	{"cntrl", ctype_base::cntrl},
 	{"digit", ctype_base::digit},
 	{"graph", ctype_base::graph},
@@ -377,11 +377,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return __fctyp.is(__f._M_base, __c)
 	// [[:w:]]
 	|| ((__f._M_extended & _RegexMask::_S_under)
-	    && __c == __fctyp.widen('_'))
-	// [[:blank:]]
-	|| ((__f._M_extended & _RegexMask::_S_blank)
-	    && (__c == __fctyp.widen(' ')
-		|| __c == __fctyp.widen('\t')));
+	    && __c == __fctyp.widen('_'));
     }
 
   template<typename _Ch_type>