diff --git a/clang/lib/Sema/DeclSpec.cpp b/clang/lib/Sema/DeclSpec.cpp
--- a/clang/lib/Sema/DeclSpec.cpp
+++ b/clang/lib/Sema/DeclSpec.cpp
@@ -1196,7 +1196,13 @@
         S.Diag(TSTLoc, diag::err_invalid_vector_float_decl_spec);
     } else if (TypeSpecWidth == TSW_long) {
       // vector long is unsupported for ZVector and deprecated for AltiVec.
-      if (S.getLangOpts().ZVector)
+      // It has also been historically deprecated on AIX (as an alias for
+      // "vector int" in both 32-bit and 64-bit modes). It was then made
+      // unsupported in the Clang-based XL compiler since the deprecated type
+      // has a number of conflicting semantics and continuing to support it
+      // is a disservice to users.
+      if (S.getLangOpts().ZVector ||
+          S.Context.getTargetInfo().getTriple().isOSAIX())
         S.Diag(TSWRange.getBegin(), diag::err_invalid_vector_long_decl_spec);
       else
         S.Diag(TSWRange.getBegin(),
diff --git a/clang/test/Parser/altivec.c b/clang/test/Parser/altivec.c
--- a/clang/test/Parser/altivec.c
+++ b/clang/test/Parser/altivec.c
@@ -1,6 +1,8 @@
-// RUN: %clang_cc1 -triple=powerpc-apple-darwin8 -target-feature +altivec -fsyntax-only -verify %s
-// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify %s
-// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple=powerpc-apple-darwin8 -target-feature +altivec -fsyntax-only -verify=expected,nonaix %s
+// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify=expected,nonaix %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify=expected,nonaix %s
+// RUN: %clang_cc1 -triple=powerpc-ibm-aix -target-feature +altivec -fsyntax-only -verify=expected,aix %s
+// RUN: %clang_cc1 -triple=powerpc64-ibm-aix -target-feature +altivec -fsyntax-only -verify=expected,aix %s
 
 __vector char vv_c;
 __vector signed char vv_sc;
@@ -54,19 +56,33 @@
 
 vector int v = (vector int)(-1);
 
+// These should have errors on AIX and warnings otherwise.
+__vector long vv_l;                 // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector signed long vv_sl;         // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector unsigned long vv_ul;       // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector long int vv_li;            // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector signed long int vv_sli;    // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector unsigned long int vv_uli;  // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector long v_l;                    // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector signed long v_sl;            // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector unsigned long v_ul;          // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector long int v_li;               // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector signed long int v_sli;       // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector unsigned long int v_uli;     // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+
 // These should have warnings.
-__vector long vv_l;                 // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector signed long vv_sl;         // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector unsigned long vv_ul;       // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector long int vv_li;            // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector signed long int vv_sli;    // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector unsigned long int vv_uli;  // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector long v_l;                    // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector signed long v_sl;            // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector unsigned long v_ul;          // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector long int v_li;               // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector signed long int v_sli;       // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector unsigned long int v_uli;     // expected-warning {{Use of 'long' with '__vector' is deprecated}}
 __vector long double  vv_ld;        // expected-error {{cannot use 'long double' with '__vector'}}
 vector long double  v_ld;           // expected-error {{cannot use 'long double' with '__vector'}}
 vector bool v_b;                    // expected-warning {{type specifier missing, defaults to 'int'}}
@@ -106,7 +122,7 @@
   // i8, i16, i32 here are field names, not type names.
   vector bool i8;                    // expected-error {{requires a specifier or qualifier}}
   vector pixel i16;
-  vector long i32;                   // expected-warning {{deprecated}}
+  vector short i32;
 };
 
 void f() {
diff --git a/clang/test/Parser/cxx-altivec.cpp b/clang/test/Parser/cxx-altivec.cpp
--- a/clang/test/Parser/cxx-altivec.cpp
+++ b/clang/test/Parser/cxx-altivec.cpp
@@ -1,6 +1,8 @@
-// RUN: %clang_cc1 -triple=powerpc-apple-darwin8 -target-feature +altivec -fsyntax-only -verify -std=c++11 %s
-// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify -std=c++11 %s
-// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc-apple-darwin8 -target-feature +altivec -fsyntax-only -verify=expected,nonaix -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc64-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify=expected,nonaix -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc64le-unknown-linux-gnu -target-feature +altivec -fsyntax-only -verify=expected,nonaix -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc-ibm-aix -target-feature +altivec -fsyntax-only -verify=expected,aix -std=c++11 %s
+// RUN: %clang_cc1 -triple=powerpc64-ibm-aix -target-feature +altivec -fsyntax-only -verify=expected,aix -std=c++11 %s
 #include <altivec.h>
 
 __vector char vv_c;
@@ -55,19 +57,33 @@
 
 vector int v = (vector int)(-1);
 
+// These should have errors on AIX and warnings otherwise.
+__vector long vv_l;                 // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector signed long vv_sl;         // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector unsigned long vv_ul;       // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector long int vv_li;            // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector signed long int vv_sli;    // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+__vector unsigned long int vv_uli;  // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector long v_l;                    // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector signed long v_sl;            // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector unsigned long v_ul;          // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector long int v_li;               // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector signed long int v_sli;       // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+vector unsigned long int v_uli;     // nonaix-warning {{Use of 'long' with '__vector' is deprecated}}
+                                    // aix-error@-1 {{cannot use 'long' with '__vector'}}
+
 // These should have warnings.
-__vector long vv_l;                 // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector signed long vv_sl;         // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector unsigned long vv_ul;       // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector long int vv_li;            // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector signed long int vv_sli;    // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-__vector unsigned long int vv_uli;  // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector long v_l;                    // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector signed long v_sl;            // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector unsigned long v_ul;          // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector long int v_li;               // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector signed long int v_sli;       // expected-warning {{Use of 'long' with '__vector' is deprecated}}
-vector unsigned long int v_uli;     // expected-warning {{Use of 'long' with '__vector' is deprecated}}
 __vector long double  vv_ld;        // expected-error {{cannot use 'long double' with '__vector'}}
 vector long double  v_ld;           // expected-error {{cannot use 'long double' with '__vector'}}