diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -80,6 +80,7 @@
 option(LIBCXX_ENABLE_FILESYSTEM "Build filesystem as part of the main libc++ library"
     ${ENABLE_FILESYSTEM_DEFAULT})
 option(LIBCXX_INCLUDE_TESTS "Build the libc++ tests." ${LLVM_INCLUDE_TESTS})
+option(LIBCXX_ENABLE_PARALLEL_ALGORITHMS "Enable the parallel algorithms library. This requires the PSTL to be available." OFF)
 
 # Benchmark options -----------------------------------------------------------
 option(LIBCXX_INCLUDE_BENCHMARKS "Build the libc++ benchmarks and their dependencies" ON)
@@ -733,6 +734,7 @@
 config_define_if(LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY _LIBCPP_HAS_THREAD_LIBRARY_EXTERNAL)
 config_define_if(LIBCXX_HAS_MUSL_LIBC _LIBCPP_HAS_MUSL_LIBC)
 config_define_if(LIBCXX_NO_VCRUNTIME _LIBCPP_NO_VCRUNTIME)
+config_define_if_not(LIBCXX_ENABLE_PARALLEL_ALGORITHMS _LIBCPP_HAS_NO_PARALLEL_ALGORITHMS)
 
 if (LIBCXX_ABI_DEFINES)
   set(abi_defines)
diff --git a/libcxx/include/__config_site.in b/libcxx/include/__config_site.in
--- a/libcxx/include/__config_site.in
+++ b/libcxx/include/__config_site.in
@@ -29,6 +29,7 @@
 #cmakedefine _LIBCPP_NO_VCRUNTIME
 #cmakedefine01 _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
 #cmakedefine _LIBCPP_ABI_NAMESPACE @_LIBCPP_ABI_NAMESPACE@
+#cmakedefine _LIBCPP_HAS_NO_PARALLEL_ALGORITHMS
 
 @_LIBCPP_ABI_DEFINES@
 
diff --git a/libcxx/include/algorithm b/libcxx/include/algorithm
--- a/libcxx/include/algorithm
+++ b/libcxx/include/algorithm
@@ -5682,4 +5682,16 @@
 
 _LIBCPP_POP_MACROS
 
+#if !defined(_LIBCPP_HAS_NO_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
+    // If <execution> has already been included, pull in implementations,
+    // otherwise just pull in forward declarations.
+#   include <pstl/internal/pstl_config.h>
+#   if defined(_PSTL_EXECUTION_POLICIES_DEFINED)
+#       include <pstl/internal/glue_algorithm_impl.h>
+#   else
+#       include <pstl/internal/glue_algorithm_defs.h>
+#       define _PSTL_ALGORITHM_FORWARD_DECLARED 1
+#   endif
+#endif
+
 #endif  // _LIBCPP_ALGORITHM
diff --git a/libcxx/include/execution b/libcxx/include/execution
new file mode 100644
--- /dev/null
+++ b/libcxx/include/execution
@@ -0,0 +1,38 @@
+// -*- C++ -*-
+//===------------------------- execution ---------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXECUTION
+#define _LIBCPP_EXECUTION
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
+
+#include <pstl/internal/pstl_config.h>
+#include <pstl/internal/execution_defs.h>
+
+#define _PSTL_EXECUTION_POLICIES_DEFINED 1
+
+#if defined(_PSTL_ALGORITHM_FORWARD_DECLARED)
+#    include <pstl/internal/glue_algorithm_impl.h>
+#endif
+
+#if defined(_PSTL_MEMORY_FORWARD_DECLARED)
+#    include <pstl/internal/glue_memory_impl.h>
+#endif
+
+#if defined(_PSTL_NUMERIC_FORWARD_DECLARED)
+#    include <pstl/internal/glue_numeric_impl.h>
+#endif
+
+#include <pstl/internal/glue_execution_defs.h>
+
+#endif // _LIBCPP_HAS_NO_PARALLEL_ALGORITHMS && C++17
+
+#endif // _LIBCPP_EXECUTION
diff --git a/libcxx/include/memory b/libcxx/include/memory
--- a/libcxx/include/memory
+++ b/libcxx/include/memory
@@ -5718,4 +5718,16 @@
 
 _LIBCPP_POP_MACROS
 
+#if !defined(_LIBCPP_HAS_NO_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
+    // If <execution> has already been included, pull in implementations,
+    // otherwise just pull in forward declarations.
+#   include <pstl/internal/pstl_config.h>
+#   if defined(_PSTL_EXECUTION_POLICIES_DEFINED)
+#       include <pstl/internal/glue_memory_impl.h>
+#   else
+#       include <pstl/internal/glue_memory_defs.h>
+#       define _PSTL_MEMORY_FORWARD_DECLARED 1
+#   endif
+#endif
+
 #endif  // _LIBCPP_MEMORY
diff --git a/libcxx/include/numeric b/libcxx/include/numeric
--- a/libcxx/include/numeric
+++ b/libcxx/include/numeric
@@ -586,4 +586,16 @@
 
 _LIBCPP_POP_MACROS
 
+#if !defined(_LIBCPP_HAS_NO_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
+    // If <execution> has already been included, pull in implementations,
+    // otherwise just pull in forward declarations.
+#   include <pstl/internal/pstl_config.h>
+#   if defined(_PSTL_EXECUTION_POLICIES_DEFINED)
+#       include <pstl/internal/glue_numeric_impl.h>
+#   else
+#       include <pstl/internal/glue_numeric_defs.h>
+#       define _PSTL_NUMERIC_FORWARD_DECLARED 1
+#   endif
+#endif
+
 #endif  // _LIBCPP_NUMERIC
diff --git a/libcxx/src/CMakeLists.txt b/libcxx/src/CMakeLists.txt
--- a/libcxx/src/CMakeLists.txt
+++ b/libcxx/src/CMakeLists.txt
@@ -194,6 +194,11 @@
   endif()
 endfunction()
 
+find_package(ParallelSTL)
+if (LIBCXX_ENABLE_PARALLEL_ALGORITHMS AND NOT TARGET pstl::ParallelSTL)
+  message(FATAL_ERROR "Could not find ParallelSTL")
+endif()
+
 function(cxx_set_common_defines name)
   if(LIBCXX_CXX_ABI_HEADER_TARGET)
     add_dependencies(${name} ${LIBCXX_CXX_ABI_HEADER_TARGET})
@@ -220,6 +225,10 @@
                                  # in printf, scanf.
                                  _CRT_STDIO_ISO_WIDE_SPECIFIERS)
   endif()
+
+  if (LIBCXX_ENABLE_PARALLEL_ALGORITHMS)
+    target_link_libraries(${name} PUBLIC pstl::ParallelSTL)
+  endif()
 endfunction()
 
 split_list(LIBCXX_COMPILE_FLAGS)
diff --git a/libcxx/test/CMakeLists.txt b/libcxx/test/CMakeLists.txt
--- a/libcxx/test/CMakeLists.txt
+++ b/libcxx/test/CMakeLists.txt
@@ -40,6 +40,7 @@
 pythonize_bool(LIBCXX_HAVE_CXX_ATOMICS_WITH_LIB)
 pythonize_bool(LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY)
 pythonize_bool(LIBCXX_DEBUG_BUILD)
+pythonize_bool(LIBCXX_ENABLE_PARALLEL_ALGORITHMS)
 
 # By default, for non-standalone builds, libcxx and libcxxabi share a library
 # directory.
diff --git a/libcxx/test/lit.site.cfg.in b/libcxx/test/lit.site.cfg.in
--- a/libcxx/test/lit.site.cfg.in
+++ b/libcxx/test/lit.site.cfg.in
@@ -33,6 +33,7 @@
 config.debug_build              = @LIBCXX_DEBUG_BUILD@
 config.libcxxabi_shared         = @LIBCXXABI_ENABLE_SHARED@
 config.cxx_ext_threads          = @LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY@
+config.pstl_root                = "@ParallelSTL_SOURCE_DIR@" if @LIBCXX_ENABLE_PARALLEL_ALGORITHMS@ else None
 
 # Let the main config do the real work.
 config.loaded_site_config = True
diff --git a/libcxx/test/std/pstl b/libcxx/test/std/pstl
new file mode 120000
--- /dev/null
+++ b/libcxx/test/std/pstl
@@ -0,0 +1 @@
+../../../pstl/test/std
\ No newline at end of file
diff --git a/libcxx/utils/libcxx/test/config.py b/libcxx/utils/libcxx/test/config.py
--- a/libcxx/utils/libcxx/test/config.py
+++ b/libcxx/utils/libcxx/test/config.py
@@ -580,6 +580,13 @@
         support_path = os.path.join(self.libcxx_src_root, 'test/support')
         self.cxx.compile_flags += ['-I' + support_path]
 
+        # Add includes for the PSTL headers
+        pstl_root = self.get_lit_conf('pstl_root')
+        if pstl_root is not None:
+            self.cxx.compile_flags += ['-I' + os.path.join(pstl_root, 'include')]
+            self.cxx.compile_flags += ['-I' + os.path.join(pstl_root, 'test')]
+            self.config.available_features.add('parallel-algorithms')
+
         # FIXME(EricWF): variant_size.pass.cpp requires a slightly larger
         # template depth with older Clang versions.
         self.cxx.addFlagIfSupported('-ftemplate-depth=270')
diff --git a/libcxxabi/src/CMakeLists.txt b/libcxxabi/src/CMakeLists.txt
--- a/libcxxabi/src/CMakeLists.txt
+++ b/libcxxabi/src/CMakeLists.txt
@@ -147,6 +147,11 @@
   string(REPLACE "-Wl,-z,defs" "" CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS}")
 endif()
 
+find_package(ParallelSTL)
+if (NOT TARGET pstl::ParallelSTL)
+  message(STATUS "Could not find ParallelSTL, libc++abi will not attempt to use it but the build may fail if the libc++ in use needs it to be available.")
+endif()
+
 # Build the shared library.
 if (LIBCXXABI_ENABLE_SHARED)
   add_library(cxxabi_shared SHARED ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
@@ -154,6 +159,9 @@
     llvm_setup_rpath(cxxabi_shared)
   endif()
   target_link_libraries(cxxabi_shared PRIVATE ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+  if (TARGET pstl::ParallelSTL)
+    target_link_libraries(cxxabi_shared PUBLIC pstl::ParallelSTL)
+  endif()
   set_target_properties(cxxabi_shared
                         PROPERTIES
                           CXX_EXTENSIONS
@@ -187,6 +195,9 @@
 if (LIBCXXABI_ENABLE_STATIC)
   add_library(cxxabi_static STATIC ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
   target_link_libraries(cxxabi_static PRIVATE ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+  if (TARGET pstl::ParallelSTL)
+    target_link_libraries(cxxabi_static PUBLIC pstl::ParallelSTL)
+  endif()
   set_target_properties(cxxabi_static
                         PROPERTIES
                           CXX_EXTENSIONS
diff --git a/llvm/projects/CMakeLists.txt b/llvm/projects/CMakeLists.txt
--- a/llvm/projects/CMakeLists.txt
+++ b/llvm/projects/CMakeLists.txt
@@ -30,8 +30,8 @@
     # Add the projects in reverse order of their dependencies so that the
     # dependent projects can see the target names of their dependencies.
     add_llvm_external_project(libunwind)
-    add_llvm_external_project(libcxxabi)
     add_llvm_external_project(pstl)
+    add_llvm_external_project(libcxxabi)
     add_llvm_external_project(libcxx)
   endif()
   if(NOT LLVM_BUILD_EXTERNAL_COMPILER_RT)
diff --git a/pstl/test/pstl/header_inclusion_order_algorithm_0.pass.cpp b/pstl/test/pstl/header_inclusion_order_algorithm_0.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_algorithm_0.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_algorithm_0.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/pstl/header_inclusion_order_algorithm_1.pass.cpp b/pstl/test/pstl/header_inclusion_order_algorithm_1.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_algorithm_1.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_algorithm_1.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/pstl/header_inclusion_order_memory_0.pass.cpp b/pstl/test/pstl/header_inclusion_order_memory_0.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_memory_0.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_memory_0.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/pstl/header_inclusion_order_memory_1.pass.cpp b/pstl/test/pstl/header_inclusion_order_memory_1.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_memory_1.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_memory_1.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/pstl/header_inclusion_order_numeric_0.pass.cpp b/pstl/test/pstl/header_inclusion_order_numeric_0.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_numeric_0.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_numeric_0.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/pstl/header_inclusion_order_numeric_1.pass.cpp b/pstl/test/pstl/header_inclusion_order_numeric_1.pass.cpp
--- a/pstl/test/pstl/header_inclusion_order_numeric_1.pass.cpp
+++ b/pstl/test/pstl/header_inclusion_order_numeric_1.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.merge/inplace_merge.pass.cpp b/pstl/test/std/algorithms/alg.merge/inplace_merge.pass.cpp
--- a/pstl/test/std/algorithms/alg.merge/inplace_merge.pass.cpp
+++ b/pstl/test/std/algorithms/alg.merge/inplace_merge.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.merge/merge.pass.cpp b/pstl/test/std/algorithms/alg.merge/merge.pass.cpp
--- a/pstl/test/std/algorithms/alg.merge/merge.pass.cpp
+++ b/pstl/test/std/algorithms/alg.merge/merge.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for copy_if and remove_copy_if
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for stable_partition and partition
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for stable_partition and partition_copy
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/copy_move.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/copy_move.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/copy_move.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/copy_move.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for copy, move and copy_n
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/fill.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/fill.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/fill.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/fill.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/generate.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/generate.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/generate.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/generate.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/remove.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/remove.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/remove.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/remove.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Test for remove, remove_if
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/remove_copy.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/remove_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/remove_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/remove_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/replace.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/replace.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/replace.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/replace.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/replace_copy.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/replace_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/replace_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/replace_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for replace_copy and replace_copy_if
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/rotate.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/rotate.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/rotate.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/rotate.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/rotate_copy.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/rotate_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/rotate_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/rotate_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/swap_ranges.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/swap_ranges.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/swap_ranges.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/swap_ranges.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/unique.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/unique.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/unique.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/unique.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Test for unique
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.modifying.operations/unique_copy_equal.pass.cpp b/pstl/test/std/algorithms/alg.modifying.operations/unique_copy_equal.pass.cpp
--- a/pstl/test/std/algorithms/alg.modifying.operations/unique_copy_equal.pass.cpp
+++ b/pstl/test/std/algorithms/alg.modifying.operations/unique_copy_equal.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for unique_copy
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/adjacent_find.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/adjacent_find.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/adjacent_find.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/adjacent_find.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/all_of.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/all_of.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/all_of.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/all_of.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/any_of.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/any_of.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/any_of.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/any_of.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/count.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/count.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/count.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/count.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for count and count_if
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/equal.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/equal.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/equal.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/equal.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/find.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/find.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/find.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/find.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for find
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/find_end.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/find_end.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/find_end.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/find_end.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/find_first_of.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/find_first_of.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/find_first_of.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/find_first_of.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/find_if.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/find_if.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/find_if.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/find_if.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for find_if and find_if_not
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/for_each.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/for_each.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/for_each.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/for_each.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/mismatch.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/mismatch.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/mismatch.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/mismatch.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/none_of.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/none_of.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/none_of.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/none_of.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/nth_element.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/nth_element.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/nth_element.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/nth_element.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.nonmodifying/search_n.pass.cpp b/pstl/test/std/algorithms/alg.nonmodifying/search_n.pass.cpp
--- a/pstl/test/std/algorithms/alg.nonmodifying/search_n.pass.cpp
+++ b/pstl/test/std/algorithms/alg.nonmodifying/search_n.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/alg.heap.operations/is_heap.pass.cpp b/pstl/test/std/algorithms/alg.sorting/alg.heap.operations/is_heap.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/alg.heap.operations/is_heap.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/alg.heap.operations/is_heap.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for is_heap, is_heap_until
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp b/pstl/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp b/pstl/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/alg.set.operations/includes.pass.cpp b/pstl/test/std/algorithms/alg.sorting/alg.set.operations/includes.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/alg.set.operations/includes.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/alg.set.operations/includes.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/alg.set.operations/set.pass.cpp b/pstl/test/std/algorithms/alg.sorting/alg.set.operations/set.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/alg.set.operations/set.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/alg.set.operations/set.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/is_sorted.pass.cpp b/pstl/test/std/algorithms/alg.sorting/is_sorted.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/is_sorted.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/is_sorted.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/partial_sort.pass.cpp b/pstl/test/std/algorithms/alg.sorting/partial_sort.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/partial_sort.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/partial_sort.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/algorithms/alg.sorting/partial_sort_copy.pass.cpp b/pstl/test/std/algorithms/alg.sorting/partial_sort_copy.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/partial_sort_copy.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/partial_sort_copy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for partial_sort_copy
 #include "support/pstl_test_config.h"
diff --git a/pstl/test/std/algorithms/alg.sorting/sort.pass.cpp b/pstl/test/std/algorithms/alg.sorting/sort.pass.cpp
--- a/pstl/test/std/algorithms/alg.sorting/sort.pass.cpp
+++ b/pstl/test/std/algorithms/alg.sorting/sort.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/numerics/numeric.ops/adjacent_difference.pass.cpp b/pstl/test/std/numerics/numeric.ops/adjacent_difference.pass.cpp
--- a/pstl/test/std/numerics/numeric.ops/adjacent_difference.pass.cpp
+++ b/pstl/test/std/numerics/numeric.ops/adjacent_difference.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/numerics/numeric.ops/reduce.pass.cpp b/pstl/test/std/numerics/numeric.ops/reduce.pass.cpp
--- a/pstl/test/std/numerics/numeric.ops/reduce.pass.cpp
+++ b/pstl/test/std/numerics/numeric.ops/reduce.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/numerics/numeric.ops/scan.pass.cpp b/pstl/test/std/numerics/numeric.ops/scan.pass.cpp
--- a/pstl/test/std/numerics/numeric.ops/scan.pass.cpp
+++ b/pstl/test/std/numerics/numeric.ops/scan.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/numerics/numeric.ops/transform_reduce.pass.cpp b/pstl/test/std/numerics/numeric.ops/transform_reduce.pass.cpp
--- a/pstl/test/std/numerics/numeric.ops/transform_reduce.pass.cpp
+++ b/pstl/test/std/numerics/numeric.ops/transform_reduce.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/numerics/numeric.ops/transform_scan.pass.cpp b/pstl/test/std/numerics/numeric.ops/transform_scan.pass.cpp
--- a/pstl/test/std/numerics/numeric.ops/transform_scan.pass.cpp
+++ b/pstl/test/std/numerics/numeric.ops/transform_scan.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"
 
diff --git a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_construct.pass.cpp b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_construct.pass.cpp
--- a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_construct.pass.cpp
+++ b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_construct.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for uninitialized_default_construct, uninitialized_default_construct_n,
 //           uninitialized_value_construct,   uninitialized_value_construct_n
diff --git a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_copy_move.pass.cpp b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_copy_move.pass.cpp
--- a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_copy_move.pass.cpp
+++ b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_copy_move.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 // Tests for uninitialized_copy, uninitialized_copy_n, uninitialized_move, uninitialized_move_n
 
diff --git a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_fill_destroy.pass.cpp b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_fill_destroy.pass.cpp
--- a/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_fill_destroy.pass.cpp
+++ b/pstl/test/std/utilities/memory/specialized.algorithms/uninitialized_fill_destroy.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: parallel-algorithms
 
 #include "support/pstl_test_config.h"