Xing Xue:  port to IBM XLC++/AIX.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@188396 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__locale b/include/__locale
index 8b0ae33..9c51f9e 100644
--- a/include/__locale
+++ b/include/__locale
@@ -21,9 +21,11 @@
 #include <locale.h>
 #ifdef _LIBCPP_MSVCRT
 # include <support/win32/locale_win32.h>
-#elif (defined(__GLIBC__) || defined(__APPLE__) || defined(__FreeBSD__) || defined(__sun__)) || defined(EMSCRIPTEN)
+#elif _AIX
+# include <support/ibm/xlocale.h>
+#elif (defined(__GLIBC__) || defined(__APPLE__) || defined(__FreeBSD__) || defined(__sun__)) || defined(EMSCRIPTEN) || defined(__IBMCPP__)
 # include <xlocale.h>
-#endif  // _WIN32 || __GLIBC__ || __APPLE__ || __FreeBSD__ || __sun__ || EMSCRIPTEN
+#endif  // _WIN32 || __GLIBC__ || __APPLE__ || __FreeBSD__ || __sun__ || EMSCRIPTEN || __IBMCPP__
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header