diff --git a/src/libstdc++-v3/config/os/gnu/ctype_inline.h b/src/libstdc++-v3/config/os/gnu/ctype_inline.h
new file mode 100644
index 00000000000..af60239382f
--- /dev/null
+++ b/src/libstdc++-v3/config/os/gnu/ctype_inline.h
@@ -0,0 +1,76 @@
+// Locale support -*- C++ -*-
+
+// Copyright (C) 2000-2022 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file bits/ctype_inline.h
+ *  This is an internal header file, included by other library headers.
+ *  Do not attempt to use it directly. @headername{locale}
+ */
+
+//
+// ISO C++ 14882: 22.1  Locales
+//
+
+// ctype bits to be inlined go here. Non-inlinable (ie virtual do_*)
+// functions go in ctype.cc
+
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+  bool
+  ctype<char>::
+  is(mask __m, char __c) const
+  { return _M_table[static_cast<unsigned char>(__c)] & __m; }
+
+  const char*
+  ctype<char>::
+  is(const char* __low, const char* __high, mask* __vec) const
+  {
+    while (__low < __high)
+      *__vec++ = _M_table[static_cast<unsigned char>(*__low++)];
+    return __high;
+  }
+
+  const char*
+  ctype<char>::
+  scan_is(mask __m, const char* __low, const char* __high) const
+  {
+    while (__low < __high
+	   && !(_M_table[static_cast<unsigned char>(*__low)] & __m))
+      ++__low;
+    return __low;
+  }
+
+  const char*
+  ctype<char>::
+  scan_not(mask __m, const char* __low, const char* __high) const
+  {
+    while (__low < __high
+	   && (_M_table[static_cast<unsigned char>(*__low)] & __m) != 0)
+      ++__low;
+    return __low;
+  }
+
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace