diff --git a/clang/test/AST/alignas_maybe_odr_cleanup.cpp b/clang/test/AST/alignas_maybe_odr_cleanup.cpp
--- a/clang/test/AST/alignas_maybe_odr_cleanup.cpp
+++ b/clang/test/AST/alignas_maybe_odr_cleanup.cpp
@@ -8,7 +8,7 @@
 // RUN: | FileCheck %s
 
 struct FOO {
-  static const int vec_align_bytes = 32;
+  static const int vec_align_bytes = 16;
   void foo() {
     double a alignas(vec_align_bytes);
     ;
@@ -17,7 +17,7 @@
 
 // CHECK:      |   `-AlignedAttr {{.*}} <col:14> alignas
 // CHECK-NEXT:      |     `-ConstantExpr {{.*}} <col:22> 'int'
-// CHECK-NEXT:      |       |-value: Int 32
+// CHECK-NEXT:      |       |-value: Int 16
 // CHECK-NEXT:      |       `-ImplicitCastExpr {{.*}} <col:22> 'int' <LValueToRValue>
 // CHECK-NEXT:      |         `-DeclRefExpr {{.*}} <col:22> 'const int' lvalue Var {{.*}} 'vec_align_bytes' 'const int' non_odr_use_constant
 // CHECK-NEXT:      `-NullStmt {{.*}} <line:14:5>
diff --git a/clang/test/CodeGen/PR5060-align.c b/clang/test/CodeGen/PR5060-align.c
--- a/clang/test/CodeGen/PR5060-align.c
+++ b/clang/test/CodeGen/PR5060-align.c
@@ -1,13 +1,13 @@
 // RUN: %clang_cc1 -emit-llvm %s -o - | FileCheck %s
 
-// CHECK: @foo.p = internal global i8 0, align 32
+// CHECK: @foo.p = internal global i8 0, align 16
 char *foo(void) {
-  static char p __attribute__((aligned(32)));
+  static char p __attribute__((aligned(16)));
   return &p;
 }
 
 void bar(long n) {
-  // CHECK: align 32
-  char p[n] __attribute__((aligned(32)));
+  // CHECK: align 16
+  char p[n] __attribute__((aligned(16)));
 }
 
diff --git a/clang/test/Layout/itanium-union-bitfield.cpp b/clang/test/Layout/itanium-union-bitfield.cpp
--- a/clang/test/Layout/itanium-union-bitfield.cpp
+++ b/clang/test/Layout/itanium-union-bitfield.cpp
@@ -1,15 +1,23 @@
 // RUN: %clang_cc1 -emit-llvm-only -triple %itanium_abi_triple -fdump-record-layouts %s 2>/dev/null \
 // RUN:            | FileCheck %s
 
+// On z/OS, a bit-field has single byte alignment.  Add aligned(4) on z/OS so the union has
+// the same size & alignment as expected.
+#ifdef __MVS__
+#define ALIGN4 __attribute__((aligned(4)))
+#else
+#define ALIGN4
+#endif
+
 union A {
-  int f1: 3;
+  int f1 : 3 ALIGN4;
   A();
 };
 
 A::A() {}
 
 union B {
-  char f1: 35;
+  char f1 : 35 ALIGN4;
   B();
 };