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/src/locale.cpp b/src/locale.cpp
index d95d0c9..ac19521 100644
--- a/src/locale.cpp
+++ b/src/locale.cpp
@@ -1015,6 +1015,8 @@
 // going to end up dereferencing it later...
 #elif defined(EMSCRIPTEN)
     return *__ctype_b_loc();
+#elif defined(_AIX)
+    return (const unsigned long *)__lc_ctype_ptr->obj->mask;
 #else
     // Platform not supported: abort so the person doing the port knows what to
     // fix