diff --git a/include/__bit_reference b/include/__bit_reference
index 857dd5a..39a9dc3 100644
--- a/include/__bit_reference
+++ b/include/__bit_reference
@@ -40,7 +40,7 @@
     __storage_pointer __seg_;
     __storage_type    __mask_;
 
-#if defined(__clang__)
+#if defined(__clang__) || defined(__IBMCPP__)
     friend typename _Cp::__self;
 #else
     friend class _Cp::__self;
@@ -130,7 +130,7 @@
     __storage_pointer        __seg_;
     __storage_type __mask_;
 
-#if defined(__clang__)
+#if defined(__clang__) || defined(__IBMCPP__)
     friend typename _Cp::__self;
 #else
     friend class _Cp::__self;
@@ -1222,7 +1222,7 @@
     __bit_iterator(__storage_pointer __s, unsigned __ctz) _NOEXCEPT
         : __seg_(__s), __ctz_(__ctz) {}
 
-#if defined(__clang__)
+#if defined(__clang__) || defined(__IBMCPP__)
     friend typename _Cp::__self;
 #else
     friend class _Cp::__self;
diff --git a/include/__config b/include/__config
index 5f68e46..46e84bc 100644
--- a/include/__config
+++ b/include/__config
@@ -434,7 +434,39 @@
 namespace std {
 }
 
-#endif // __clang__ || __GNUC__ || _LIBCPP_MSVC
+#elif defined(__IBMCPP__)
+
+#define _ALIGNAS(x) __attribute__((__aligned__(x)))
+#define _ALIGNAS_TYPE(x) __attribute__((__aligned__(__alignof(x))))
+#define _ATTRIBUTE(x) __attribute__((x))
+#define _LIBCPP_NORETURN __attribute__((noreturn))
+
+#define _NOEXCEPT throw()
+#define _NOEXCEPT_(x)
+
+#define _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+#define _LIBCPP_HAS_NO_ADVANCED_SFINAE
+#define _LIBCPP_HAS_NO_ALWAYS_INLINE_VARIADICS
+#define _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
+#define _LIBCPP_HAS_NO_NULLPTR
+#define _LIBCPP_HAS_NO_UNICODE_CHARS
+#define _LIBCPP_HAS_NO_STRONG_ENUMS
+#define _LIBCPP_HAS_IS_BASE_OF
+
+#if defined(_AIX)
+#define __MULTILOCALE_API
+#endif
+
+#define _LIBCPP_BEGIN_NAMESPACE_STD namespace std {inline namespace _LIBCPP_NAMESPACE {
+#define _LIBCPP_END_NAMESPACE_STD  } }
+#define _VSTD std::_LIBCPP_NAMESPACE
+
+namespace std {
+  inline namespace _LIBCPP_NAMESPACE {
+  }
+}
+
+#endif // __clang__ || __GNUC___ || _MSC_VER || __IBMCPP__
 
 #ifdef _LIBCPP_HAS_NO_UNICODE_CHARS
 typedef unsigned short char16_t;
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
diff --git a/include/algorithm b/include/algorithm
index adf820f..053b809 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -628,6 +628,10 @@
 #include <iterator>
 #include <cstddef>
 
+#if defined(__IBMCPP__)
+#include "support/ibm/support.h"
+#endif
+
 #include <__undef_min_max>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
diff --git a/include/cmath b/include/cmath
index 3e545ce..f253b93 100644
--- a/include/cmath
+++ b/include/cmath
@@ -654,6 +654,7 @@
 
 // abs
 
+#if !defined(_AIX)
 inline _LIBCPP_INLINE_VISIBILITY
 float
 abs(float __x) _NOEXCEPT {return fabsf(__x);}
@@ -665,6 +666,7 @@
 inline _LIBCPP_INLINE_VISIBILITY
 long double
 abs(long double __x) _NOEXCEPT {return fabsl(__x);}
+#endif // !defined(_AIX)
 
 #ifndef __sun__
 
@@ -673,7 +675,7 @@
 using ::acos;
 using ::acosf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       acos(float __x) _NOEXCEPT       {return acosf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double acos(long double __x) _NOEXCEPT {return acosl(__x);}
 #endif
@@ -688,7 +690,7 @@
 using ::asin;
 using ::asinf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       asin(float __x) _NOEXCEPT       {return asinf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double asin(long double __x) _NOEXCEPT {return asinl(__x);}
 #endif
@@ -703,7 +705,7 @@
 using ::atan;
 using ::atanf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       atan(float __x) _NOEXCEPT       {return atanf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double atan(long double __x) _NOEXCEPT {return atanl(__x);}
 #endif
@@ -718,7 +720,7 @@
 using ::atan2;
 using ::atan2f;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       atan2(float __y, float __x) _NOEXCEPT             {return atan2f(__y, __x);}
 inline _LIBCPP_INLINE_VISIBILITY long double atan2(long double __y, long double __x) _NOEXCEPT {return atan2l(__y, __x);}
 #endif
@@ -744,7 +746,7 @@
 using ::ceil;
 using ::ceilf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       ceil(float __x) _NOEXCEPT       {return ceilf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double ceil(long double __x) _NOEXCEPT {return ceill(__x);}
 #endif
@@ -759,7 +761,7 @@
 using ::cos;
 using ::cosf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       cos(float __x) _NOEXCEPT       {return cosf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double cos(long double __x) _NOEXCEPT {return cosl(__x);}
 #endif
@@ -774,7 +776,7 @@
 using ::cosh;
 using ::coshf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       cosh(float __x) _NOEXCEPT       {return coshf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double cosh(long double __x) _NOEXCEPT {return coshl(__x);}
 #endif
@@ -792,7 +794,7 @@
 
 #ifndef __sun__
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       exp(float __x) _NOEXCEPT       {return expf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double exp(long double __x) _NOEXCEPT {return expl(__x);}
 #endif
@@ -808,7 +810,7 @@
 using ::fabs;
 using ::fabsf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       fabs(float __x) _NOEXCEPT       {return fabsf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double fabs(long double __x) _NOEXCEPT {return fabsl(__x);}
 #endif
@@ -823,7 +825,7 @@
 using ::floor;
 using ::floorf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       floor(float __x) _NOEXCEPT       {return floorf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double floor(long double __x) _NOEXCEPT {return floorl(__x);}
 #endif
@@ -840,7 +842,7 @@
 using ::fmodf;
 #ifndef __sun__
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       fmod(float __x, float __y) _NOEXCEPT             {return fmodf(__x, __y);}
 inline _LIBCPP_INLINE_VISIBILITY long double fmod(long double __x, long double __y) _NOEXCEPT {return fmodl(__x, __y);}
 #endif
@@ -867,7 +869,7 @@
 using ::frexp;
 using ::frexpf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       frexp(float __x, int* __e) _NOEXCEPT       {return frexpf(__x, __e);}
 inline _LIBCPP_INLINE_VISIBILITY long double frexp(long double __x, int* __e) _NOEXCEPT {return frexpl(__x, __e);}
 #endif
@@ -882,7 +884,7 @@
 using ::ldexp;
 using ::ldexpf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       ldexp(float __x, int __e) _NOEXCEPT       {return ldexpf(__x, __e);}
 inline _LIBCPP_INLINE_VISIBILITY long double ldexp(long double __x, int __e) _NOEXCEPT {return ldexpl(__x, __e);}
 #endif
@@ -899,7 +901,7 @@
 using ::logf;
 #ifndef __sun__
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       log(float __x) _NOEXCEPT       {return logf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double log(long double __x) _NOEXCEPT {return logl(__x);}
 #endif
@@ -915,7 +917,7 @@
 using ::log10;
 using ::log10f;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       log10(float __x) _NOEXCEPT       {return log10f(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double log10(long double __x) _NOEXCEPT {return log10l(__x);}
 #endif
@@ -930,7 +932,7 @@
 using ::modf;
 using ::modff;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       modf(float __x, float* __y) _NOEXCEPT             {return modff(__x, __y);}
 inline _LIBCPP_INLINE_VISIBILITY long double modf(long double __x, long double* __y) _NOEXCEPT {return modfl(__x, __y);}
 #endif
@@ -943,7 +945,7 @@
 
 #ifndef __sun__
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       pow(float __x, float __y) _NOEXCEPT             {return powf(__x, __y);}
 inline _LIBCPP_INLINE_VISIBILITY long double pow(long double __x, long double __y) _NOEXCEPT {return powl(__x, __y);}
 #endif
@@ -970,7 +972,7 @@
 using ::sin;
 using ::sinf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       sin(float __x) _NOEXCEPT       {return sinf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double sin(long double __x) _NOEXCEPT {return sinl(__x);}
 #endif
@@ -985,7 +987,7 @@
 using ::sinh;
 using ::sinhf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       sinh(float __x) _NOEXCEPT       {return sinhf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double sinh(long double __x) _NOEXCEPT {return sinhl(__x);}
 #endif
@@ -1002,7 +1004,7 @@
 using ::sqrtf;
 
 
-#if !(defined(_LIBCPP_MSVCRT) || defined(__sun__))
+#if !(defined(_LIBCPP_MSVCRT) || defined(__sun__) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       sqrt(float __x) _NOEXCEPT       {return sqrtf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double sqrt(long double __x) _NOEXCEPT {return sqrtl(__x);}
 #endif
@@ -1018,7 +1020,7 @@
 using ::tanf;
 #ifndef __sun__
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       tan(float __x) _NOEXCEPT       {return tanf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double tan(long double __x) _NOEXCEPT {return tanl(__x);}
 #endif
@@ -1033,7 +1035,7 @@
 using ::tanh;
 using ::tanhf;
 
-#ifndef _LIBCPP_MSVCRT
+#if !(defined(_LIBCPP_MSVCRT) || defined(_AIX))
 inline _LIBCPP_INLINE_VISIBILITY float       tanh(float __x) _NOEXCEPT       {return tanhf(__x);}
 inline _LIBCPP_INLINE_VISIBILITY long double tanh(long double __x) _NOEXCEPT {return tanhl(__x);}
 #endif
diff --git a/include/cstdlib b/include/cstdlib
index 0a96fb0..152b891 100644
--- a/include/cstdlib
+++ b/include/cstdlib
@@ -155,7 +155,7 @@
 #endif
 
 // MSVCRT already has the correct prototype in <stdlib.h> #ifdef __cplusplus
-#if !defined(_LIBCPP_MSVCRT) && !defined(__sun__)
+#if !defined(_LIBCPP_MSVCRT) && !defined(__sun__) && !defined(_AIX)
 inline _LIBCPP_INLINE_VISIBILITY long      abs(     long __x) _NOEXCEPT {return  labs(__x);}
 #ifndef _LIBCPP_HAS_NO_LONG_LONG
 inline _LIBCPP_INLINE_VISIBILITY long long abs(long long __x) _NOEXCEPT {return llabs(__x);}
diff --git a/include/limits b/include/limits
index 3fc0e6f..d917c57 100644
--- a/include/limits
+++ b/include/limits
@@ -115,6 +115,10 @@
 #include "support/win32/limits_win32.h"
 #endif // _LIBCPP_MSVCRT
 
+#if defined(__IBMCPP__)
+#include "support/ibm/limits.h"
+#endif // __IBMCPP__
+
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 enum float_round_style
diff --git a/include/locale b/include/locale
index 20dc16e..8877192 100644
--- a/include/locale
+++ b/include/locale
@@ -224,7 +224,7 @@
 // OSX has nice foo_l() functions that let you turn off use of the global
 // locale.  Linux, not so much.  The following functions avoid the locale when
 // that's possible and otherwise do the wrong thing.  FIXME.
-#if defined(__linux__) || defined(EMSCRIPTEN)
+#if defined(__linux__) || defined(EMSCRIPTEN) || defined(_AIX)
 
 #ifdef _LIBCPP_LOCALE__L_EXTENSIONS
 decltype(MB_CUR_MAX_L(_VSTD::declval<locale_t>()))
diff --git a/include/random b/include/random
index 7fc2167..c5f7584 100644
--- a/include/random
+++ b/include/random
@@ -5901,8 +5901,8 @@
         discrete_distribution(size_t __nw, double __xmin, double __xmax,
                               _UnaryOperation __fw)
         : __p_(__nw, __xmin, __xmax, __fw) {}
-    explicit discrete_distribution(const param_type& __p)
     _LIBCPP_INLINE_VISIBILITY
+    explicit discrete_distribution(const param_type& __p)
         : __p_(__p) {}
     _LIBCPP_INLINE_VISIBILITY
     void reset() {}
diff --git a/include/string b/include/string
index c5ed95c..7439b56 100644
--- a/include/string
+++ b/include/string
@@ -1615,13 +1615,13 @@
 
     template <size_type __a> static
         _LIBCPP_INLINE_VISIBILITY
-        size_type __align(size_type __s) _NOEXCEPT
+        size_type __align_it(size_type __s) _NOEXCEPT
             {return __s + (__a-1) & ~(__a-1);}
     enum {__alignment = 16};
     static _LIBCPP_INLINE_VISIBILITY
     size_type __recommend(size_type __s) _NOEXCEPT
         {return (__s < __min_cap ? __min_cap :
-                 __align<sizeof(value_type) < __alignment ?
+                 __align_it<sizeof(value_type) < __alignment ?
                             __alignment/sizeof(value_type) : 1 > (__s+1)) - 1;}
 
     void __init(const value_type* __s, size_type __sz, size_type __reserve);
diff --git a/include/support/ibm/limits.h b/include/support/ibm/limits.h
new file mode 100644
index 0000000..efdb359
--- /dev/null
+++ b/include/support/ibm/limits.h
@@ -0,0 +1,99 @@
+// -*- C++ -*-
+//===--------------------- support/ibm/limits.h ---------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SUPPORT_IBM_LIMITS_H
+#define _LIBCPP_SUPPORT_IBM_LIMITS_H
+
+#if !defined(_AIX) // Linux
+#include <math.h> // for HUGE_VAL, HUGE_VALF, HUGE_VALL, and NAN
+
+static const unsigned int _QNAN_F = 0x7fc00000;
+#define NANF (*((float *)(&_QNAN_F)))
+static const unsigned int _QNAN_LDBL128[4] = {0x7ff80000, 0x0, 0x0, 0x0};
+#define NANL (*((long double *)(&_QNAN_LDBL128)))
+static const unsigned int _SNAN_F= 0x7f855555;
+#define NANSF (*((float *)(&_SNAN_F)))
+static const unsigned int _SNAN_D[2] = {0x7ff55555, 0x55555555};
+#define NANS (*((double *)(&_SNAN_D)))
+static const unsigned int _SNAN_LDBL128[4] = {0x7ff55555, 0x55555555, 0x0, 0x0};
+#define NANSL (*((long double *)(&_SNAN_LDBL128)))
+
+#define __builtin_huge_val()     HUGE_VAL
+#define __builtin_huge_valf()    HUGE_VALF
+#define __builtin_huge_vall()    HUGE_VALL
+#define __builtin_nan(__dummy)   NAN
+#define __builtin_nanf(__dummy)  NANF
+#define __builtin_nanl(__dummy)  NANL
+#define __builtin_nans(__dummy)  NANS
+#define __builtin_nansf(__dummy) NANSF
+#define __builtin_nansl(__dummy) NANSL
+
+#else
+
+#include <math.h>
+#include <float.h> // limit constants
+
+#define __builtin_huge_val()     HUGE_VAL  //0x7ff0000000000000
+#define __builtin_huge_valf()    HUGE_VALF //0x7f800000
+#define __builtin_huge_vall()    HUGE_VALL //0x7ff0000000000000
+#define __builtin_nan(__dummy)   nan(__dummy) //0x7ff8000000000000
+#define __builtin_nanf(__dummy)  nanf(__dummy) // 0x7ff80000
+#define __builtin_nanl(__dummy)  nanl(__dummy) //0x7ff8000000000000
+#define __builtin_nans(__dummy)  DBL_SNAN //0x7ff5555555555555
+#define __builtin_nansf(__dummy) FLT_SNAN //0x7f855555
+#define __builtin_nansl(__dummy) DBL_SNAN //0x7ff5555555555555
+
+#define __FLT_MANT_DIG__   FLT_MANT_DIG
+#define __FLT_DIG__        FLT_DIG
+#define __FLT_RADIX__      FLT_RADIX
+#define __FLT_MIN_EXP__    FLT_MIN_EXP
+#define __FLT_MIN_10_EXP__ FLT_MIN_10_EXP
+#define __FLT_MAX_EXP__    FLT_MAX_EXP
+#define __FLT_MAX_10_EXP__ FLT_MAX_10_EXP
+#define __FLT_MIN__        FLT_MIN
+#define __FLT_MAX__        FLT_MAX
+#define __FLT_EPSILON__    FLT_EPSILON
+// predefined by XLC on LoP
+#define __FLT_DENORM_MIN__ 1.40129846e-45F
+
+#define __DBL_MANT_DIG__   DBL_MANT_DIG
+#define __DBL_DIG__        DBL_DIG
+#define __DBL_MIN_EXP__    DBL_MIN_EXP
+#define __DBL_MIN_10_EXP__ DBL_MIN_10_EXP
+#define __DBL_MAX_EXP__    DBL_MAX_EXP
+#define __DBL_MAX_10_EXP__ DBL_MAX_10_EXP
+#define __DBL_MIN__        DBL_MIN
+#define __DBL_MAX__        DBL_MAX
+#define __DBL_EPSILON__    DBL_EPSILON
+// predefined by XLC on LoP
+#define __DBL_DENORM_MIN__ 4.9406564584124654e-324
+
+#define __LDBL_MANT_DIG__   LDBL_MANT_DIG
+#define __LDBL_DIG__        LDBL_DIG
+#define __LDBL_MIN_EXP__    LDBL_MIN_EXP
+#define __LDBL_MIN_10_EXP__ LDBL_MIN_10_EXP
+#define __LDBL_MAX_EXP__    LDBL_MAX_EXP
+#define __LDBL_MAX_10_EXP__ LDBL_MAX_10_EXP
+#define __LDBL_MIN__        LDBL_MIN
+#define __LDBL_MAX__        LDBL_MAX
+#define __LDBL_EPSILON__    LDBL_EPSILON
+// predefined by XLC on LoP
+#if __LONGDOUBLE128
+#define __LDBL_DENORM_MIN__ 4.94065645841246544176568792868221e-324L
+#else
+#define __LDBL_DENORM_MIN__ 4.9406564584124654e-324L
+#endif
+
+// predefined by XLC on LoP
+#define __CHAR_BIT__    8
+
+#endif // _AIX
+
+#endif // _LIBCPP_SUPPORT_IBM_LIMITS_H
diff --git a/include/support/ibm/support.h b/include/support/ibm/support.h
new file mode 100644
index 0000000..3effbae
--- /dev/null
+++ b/include/support/ibm/support.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------- support/ibm/support.h ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SUPPORT_IBM_SUPPORT_H
+#define _LIBCPP_SUPPORT_IBM_SUPPORT_H
+
+extern "builtin" int __popcnt4(unsigned int);
+extern "builtin" int __popcnt8(unsigned long long);
+extern "builtin" unsigned int __cnttz4(unsigned int);
+extern "builtin" unsigned int __cnttz8(unsigned long long);
+extern "builtin" unsigned int __cntlz4(unsigned long long);
+extern "builtin" unsigned int __cntlz8(unsigned long long);
+
+// Builtin functions for counting population
+#define __builtin_popcount(x) __popcnt4(x)
+#define __builtin_popcountll(x) __popcnt8(x)
+#if defined(__64BIT__)
+#define __builtin_popcountl(x) __builtin_popcountll(x)
+#else
+#define __builtin_popcountl(x) __builtin_popcount(x)
+#endif
+
+// Builtin functions for counting trailing zeros
+#define __builtin_ctz(x) __cnttz4(x)
+#define __builtin_ctzll(x) __cnttz8(x)
+#if defined(__64BIT__)
+#define __builtin_ctzl(x) __builtin_ctzll(x)
+#else
+#define __builtin_ctzl(x) __builtin_ctz(x)
+#endif
+
+// Builtin functions for counting leading zeros
+#define __builtin_clz(x) __cntlz4(x)
+#define __builtin_clzll(x) __cntlz8(x)
+#if defined(__64BIT__)
+#define __builtin_clzl(x) __builtin_clzll(x)
+#else
+#define __builtin_clzl(x) __builtin_clz(x)
+#endif
+
+#if defined(__64BIT__)
+#define __SIZE_WIDTH__ 64
+#else
+#define __SIZE_WIDTH__ 32
+#endif
+
+#endif // _LIBCPP_SUPPORT_IBM_SUPPORT_H
diff --git a/include/support/ibm/xlocale.h b/include/support/ibm/xlocale.h
new file mode 100644
index 0000000..fa349e0
--- /dev/null
+++ b/include/support/ibm/xlocale.h
@@ -0,0 +1,328 @@
+// -*- C++ -*-
+//===--------------------- support/ibm/xlocale.h -------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SUPPORT_IBM_XLOCALE_H
+#define _LIBCPP_SUPPORT_IBM_XLOCALE_H
+
+#if defined(_AIX)
+#include "cstdlib"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if !defined(_AIX71)
+// AIX 7.1 and higher has these definitions.  Definitions and stubs
+// are provied here as a temporary workaround on AIX 6.1.
+
+#define LC_COLLATE_MASK         1
+#define LC_CTYPE_MASK           2
+#define LC_MESSAGES_MASK        4
+#define LC_MONETARY_MASK        8
+#define LC_NUMERIC_MASK         16
+#define LC_TIME_MASK            32
+#define LC_ALL_MASK             (LC_COLLATE_MASK | LC_CTYPE_MASK | \
+                                 LC_MESSAGES_MASK | LC_MONETARY_MASK |\
+                                 LC_NUMERIC_MASK | LC_TIME_MASK)
+
+typedef void* locale_t;
+
+// The following are stubs.  They are not supported on AIX 6.1.
+static inline
+locale_t newlocale(int category_mask, const char *locale, locale_t base)
+{
+  _LC_locale_t *newloc, *loc;
+  if ((loc = (_LC_locale_t *)__xopen_locale(locale)) == NULL)
+  {
+    errno = EINVAL;
+    return (locale_t)0;
+  }
+  if ((newloc = (_LC_locale_t *)calloc(1, sizeof(_LC_locale_t))) == NULL)
+  {
+    errno = ENOMEM;
+    return (locale_t)0;
+  }
+  if (!base)
+    base = (_LC_locale_t *)__xopen_locale("C");
+  memcpy(newloc, base, sizeof (_LC_locale_t));
+  if (category_mask & LC_COLLATE_MASK) 
+    newloc->lc_collate = loc->lc_collate;
+  if (category_mask & LC_CTYPE_MASK)
+    newloc->lc_ctype = loc->lc_ctype;
+  //if (category_mask & LC_MESSAGES_MASK)
+  //  newloc->lc_messages = loc->lc_messages;
+  if (category_mask & LC_MONETARY_MASK)
+    newloc->lc_monetary = loc->lc_monetary;
+  if (category_mask & LC_TIME_MASK)
+    newloc->lc_time = loc->lc_time;
+  if (category_mask & LC_NUMERIC_MASK)
+    newloc->lc_numeric = loc->lc_numeric;
+  return (locale_t)newloc; 
+}
+static inline
+void freelocale(locale_t locobj)
+{
+  free(locobj);
+}
+static inline
+locale_t uselocale(locale_t newloc)
+{
+  return (locale_t)0;
+}
+
+static inline
+int isalnum_l(int c, locale_t locale)
+{
+  return __xisalnum(locale, c);
+}
+static inline
+int isalpha_l(int c, locale_t locale)
+{
+  return __xisalpha(locale, c);
+}
+static inline
+int isblank_l(int c, locale_t locale)
+{
+  return __xisblank(locale, c);
+}
+static inline
+int iscntrl_l(int c, locale_t locale)
+{
+  return __xiscntrl(locale, c);
+}
+static inline
+int isdigit_l(int c, locale_t locale)
+{
+  return __xisdigit(locale, c);
+}
+static inline
+int isgraph_l(int c, locale_t locale)
+{
+  return __xisgraph(locale, c);
+}
+static inline
+int islower_l(int c, locale_t locale)
+{
+  return __xislower(locale, c);
+}
+static inline
+int isprint_l(int c, locale_t locale)
+{
+  return __xisprint(locale, c);
+}
+
+static inline
+int ispunct_l(int c, locale_t locale)
+{
+  return __xispunct(locale, c);
+}
+static inline
+int isspace_l(int c, locale_t locale)
+{
+  return __xisspace(locale, c);
+}
+static inline
+int isupper_l(int c, locale_t locale)
+{
+  return __xisupper(locale, c);
+}
+
+static inline
+int isxdigit_l(int c, locale_t locale)
+{
+  return __xisxdigit(locale, c);
+}
+
+static inline
+int iswalnum_l(wchar_t wc, locale_t locale)
+{
+  return __xiswalnum(locale, wc); 
+}
+
+static inline
+int iswalpha_l(wchar_t wc, locale_t locale)
+{
+  return __xiswalpha(locale, wc);
+}
+
+static inline
+int iswblank_l(wchar_t wc, locale_t locale)
+{
+  return __xiswblank(locale, wc);
+}
+
+static inline
+int iswcntrl_l(wchar_t wc, locale_t locale)
+{
+  return __xiswcntrl(locale, wc);
+}
+
+static inline
+int iswdigit_l(wchar_t wc, locale_t locale)
+{
+  return __xiswdigit(locale, wc);
+}
+
+static inline
+int iswgraph_l(wchar_t wc, locale_t locale)
+{
+  return __xiswgraph(locale, wc);
+}
+
+static inline
+int iswlower_l(wchar_t wc, locale_t locale)
+{
+  return __xiswlower(locale, wc);
+}
+
+static inline
+int iswprint_l(wchar_t wc, locale_t locale)
+{
+  return __xiswprint(locale, wc);
+}
+
+static inline
+int iswpunct_l(wchar_t wc, locale_t locale)
+{
+  return __xiswpunct(locale, wc);
+}
+
+static inline
+int iswspace_l(wchar_t wc, locale_t locale)
+{
+  return __xiswspace(locale, wc);
+}
+
+static inline
+int iswupper_l(wchar_t wc, locale_t locale)
+{
+  return __xiswupper(locale, wc);
+}
+
+static inline
+int iswxdigit_l(wchar_t wc, locale_t locale)
+{
+  return __xiswxdigit(locale, wc);
+}
+
+static inline
+int iswctype_l(wint_t wc, wctype_t desc, locale_t locale)
+{
+  return __xiswctype(locale, wc, desc); 
+}
+
+static inline
+int toupper_l(int c, locale_t locale)
+{
+  return __xtoupper(locale, c);
+}
+static inline
+int tolower_l(int c, locale_t locale)
+{
+  return __xtolower(locale, c);
+}
+static inline
+wint_t towupper_l(wint_t wc, locale_t locale)
+{
+  return __xtowupper(locale, wc);
+}
+static inline
+wint_t towlower_l(wint_t wc, locale_t locale)
+{
+  return __xtowlower(locale, wc);
+}
+
+static inline
+int strcoll_l(const char *__s1, const char *__s2, locale_t locale)
+{
+  return __xstrcoll(locale, __s1, __s2);
+}
+static inline
+int wcscoll_l(const wchar_t *__s1, const wchar_t *__s2, locale_t locale)
+{
+  return __xwcscoll(locale, __s1, __s2);
+}
+static inline
+size_t strxfrm_l(char *__s1, const char *__s2, size_t __n, locale_t locale)
+{
+  return __xstrxfrm(locale, __s1, __s2, __n);
+}
+
+static inline
+size_t wcsxfrm_l(wchar_t *__ws1, const wchar_t *__ws2, size_t __n,
+    locale_t locale)
+{
+  return __xwcsxfrm(locale, __ws1, __ws2, __n);
+}
+#endif // !defined(_AIX71)
+
+locale_t cloc(void);
+
+// strftime_l() is defined by POSIX. However, AIX 7.1 does not have it
+// implemented yet.
+static inline
+size_t strftime_l(char *__s, size_t __size, const char *__fmt,
+                  const struct tm *__tm, locale_t locale) {
+  return __xstrftime(locale, __s, __size, __fmt, __tm);
+}
+
+// The following are not POSIX routines.  These are quick-and-dirty hacks
+// to make things pretend to work
+static inline
+long long strtoll_l(const char *__nptr, char **__endptr,
+    int __base, locale_t locale) {
+  return strtoll(__nptr, __endptr, __base);
+}
+static inline
+long strtol_l(const char *__nptr, char **__endptr,
+    int __base, locale_t locale) {
+  return strtol(__nptr, __endptr, __base);
+}
+static inline
+long double strtold_l(const char *__nptr, char **__endptr,
+    locale_t locale) {
+  return strtold(__nptr, __endptr);
+}
+static inline
+unsigned long long strtoull_l(const char *__nptr, char **__endptr,
+    int __base, locale_t locale) {
+  return strtoull(__nptr, __endptr, __base);
+}
+static inline
+unsigned long strtoul_l(const char *__nptr, char **__endptr,
+    int __base, locale_t locale) {
+  return strtoul(__nptr, __endptr, __base);
+}
+
+static inline
+int vasprintf(char **strp, const char *fmt, va_list ap)
+{
+  const size_t buff_size = 256;
+  int str_size;
+  if ((*strp = (char *)malloc(buff_size)) == NULL)
+  {
+    return -1;
+  }
+  if ((str_size = vsnprintf(*strp, buff_size, fmt,  ap)) >= buff_size)
+  {
+    if ((*strp = (char *)realloc(*strp, str_size + 1)) == NULL)
+    {
+      return -1;
+    }
+    str_size = vsnprintf(*strp, str_size + 1, fmt,  ap);
+  }
+  return str_size;
+}  
+
+#ifdef __cplusplus
+}
+#endif
+#endif // defined(_AIX)
+#endif // _LIBCPP_SUPPORT_IBM_XLOCALE_H
diff --git a/include/vector b/include/vector
index 0855e8b..2915e12 100644
--- a/include/vector
+++ b/include/vector
@@ -2281,7 +2281,7 @@
     void allocate(size_type __n);
     void deallocate() _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
-    static size_type __align(size_type __new_size) _NOEXCEPT
+    static size_type __align_it(size_type __new_size) _NOEXCEPT
         {return __new_size + (__bits_per_word-1) & ~(__bits_per_word-1);};
     _LIBCPP_INLINE_VISIBILITY  size_type __recommend(size_type __new_size) const;
     _LIBCPP_INLINE_VISIBILITY void __construct_at_end(size_type __n, bool __x);
@@ -2454,7 +2454,7 @@
     const size_type __cap = capacity();
     if (__cap >= __ms / 2)
         return __ms;
-    return _VSTD::max(2*__cap, __align(__new_size));
+    return _VSTD::max(2*__cap, __align_it(__new_size));
 }
 
 //  Default constructs __n objects starting at __end_