diff --git a/libstdc++-v3/testsuite/17_intro/names.cc b/libstdc++-v3/testsuite/17_intro/names.cc
index 9932dea14d5..eb4d064177c 100644
--- a/libstdc++-v3/testsuite/17_intro/names.cc
+++ b/libstdc++-v3/testsuite/17_intro/names.cc
@@ -243,6 +243,8 @@
 #undef v
 // <sys/timer.h> defines trb::func and cputime_tmr::func
 #undef func
+// <sys/thread.h> defines tstate::policy
+#undef policy
 #endif
 
 #ifdef __APPLE__
diff --git a/libstdc++-v3/testsuite/19_diagnostics/error_code/cons/lwg3629.cc b/libstdc++-v3/testsuite/19_diagnostics/error_code/cons/lwg3629.cc
index 70fa5e80503..bd7c6ce3d9e 100644
--- a/libstdc++-v3/testsuite/19_diagnostics/error_code/cons/lwg3629.cc
+++ b/libstdc++-v3/testsuite/19_diagnostics/error_code/cons/lwg3629.cc
@@ -3,18 +3,18 @@
 // 3629. make_error_code and make_error_condition are customization points
 // Verify that make_error_code is looked up using ADL only.
 
-namespace user
+namespace User
 {
   struct E1;
 }
 
 // N.B. not in associated namespace of E1, and declared before <system_error>.
-user::E1 make_error_code(user::E1);
+User::E1 make_error_code(User::E1);
 
 #include <future> // declares std::make_error_code(future_errc)
 #include <system_error>
 
-namespace user
+namespace User
 {
   struct E1
   {
@@ -32,17 +32,17 @@ namespace user
   };
 }
 
-template<> struct std::is_error_code_enum<user::E1> : std::true_type { };
-template<> struct std::is_error_code_enum<user::E2> : std::true_type { };
-template<> struct std::is_error_code_enum<user::E3> : std::true_type { };
+template<> struct std::is_error_code_enum<User::E1> : std::true_type { };
+template<> struct std::is_error_code_enum<User::E2> : std::true_type { };
+template<> struct std::is_error_code_enum<User::E3> : std::true_type { };
 
 // ::make_error_code(E1) should not be found by name lookup.
-std::error_code e1( user::E1{} ); // { dg-error "here" }
+std::error_code e1( User::E1{} ); // { dg-error "here" }
 
 // std::make_error_code(future_errc) should not be found by name lookup.
-std::error_code e2( user::E2{} ); // { dg-error "here" }
+std::error_code e2( User::E2{} ); // { dg-error "here" }
 
 // std::make_error_code(errc) should not be found by name lookup.
-std::error_code e3( user::E3{} ); // { dg-error "here" }
+std::error_code e3( User::E3{} ); // { dg-error "here" }
 
 // { dg-error "use of deleted function" "" { target *-*-* } 0 }
diff --git a/libstdc++-v3/testsuite/19_diagnostics/error_condition/cons/lwg3629.cc b/libstdc++-v3/testsuite/19_diagnostics/error_condition/cons/lwg3629.cc
index 562a99aee3b..d72163b1a07 100644
--- a/libstdc++-v3/testsuite/19_diagnostics/error_condition/cons/lwg3629.cc
+++ b/libstdc++-v3/testsuite/19_diagnostics/error_condition/cons/lwg3629.cc
@@ -3,18 +3,18 @@
 // 3629. make_error_code and make_error_condition are customization points
 // Verify that make_error_condition is looked up using ADL only.
 
-namespace user
+namespace User
 {
   struct E1;
 }
 
 // N.B. not in associated namespace of E1, and declared before <system_error>.
-user::E1 make_error_condition(user::E1);
+User::E1 make_error_condition(User::E1);
 
 #include <future> // declares std::make_error_condition(future_errc)
 #include <system_error>
 
-namespace user
+namespace User
 {
   struct E1
   {
@@ -32,17 +32,17 @@ namespace user
   };
 }
 
-template<> struct std::is_error_condition_enum<user::E1> : std::true_type { };
-template<> struct std::is_error_condition_enum<user::E2> : std::true_type { };
-template<> struct std::is_error_condition_enum<user::E3> : std::true_type { };
+template<> struct std::is_error_condition_enum<User::E1> : std::true_type { };
+template<> struct std::is_error_condition_enum<User::E2> : std::true_type { };
+template<> struct std::is_error_condition_enum<User::E3> : std::true_type { };
 
 // ::make_error_condition(E1) should not be found by name lookup.
-std::error_condition e1( user::E1{} ); // { dg-error "here" }
+std::error_condition e1( User::E1{} ); // { dg-error "here" }
 
 // std::make_error_condition(future_errc) should not be found by name lookup.
-std::error_condition e2( user::E2{} ); // { dg-error "here" }
+std::error_condition e2( User::E2{} ); // { dg-error "here" }
 
 // std::make_error_condition(errc) should not be found by name lookup.
-std::error_condition e3( user::E3{} ); // { dg-error "here" }
+std::error_condition e3( User::E3{} ); // { dg-error "here" }
 
 // { dg-error "use of deleted function" "" { target *-*-* } 0 }
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_map/96088.cc b/libstdc++-v3/testsuite/23_containers/unordered_map/96088.cc
index 754b529c67c..c6d50c20fbf 100644
--- a/libstdc++-v3/testsuite/23_containers/unordered_map/96088.cc
+++ b/libstdc++-v3/testsuite/23_containers/unordered_map/96088.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++17 } }
 // { dg-require-effective-target std_allocator_new }
+// { dg-xfail-run-if "AIX operator new" { powerpc-ibm-aix* } }
 
 // Copyright (C) 2021-2023 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_multimap/96088.cc b/libstdc++-v3/testsuite/23_containers/unordered_multimap/96088.cc
index b55afdfd74a..214bc91a559 100644
--- a/libstdc++-v3/testsuite/23_containers/unordered_multimap/96088.cc
+++ b/libstdc++-v3/testsuite/23_containers/unordered_multimap/96088.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++17 } }
 // { dg-require-effective-target std_allocator_new }
+// { dg-xfail-run-if "AIX operator new" { powerpc-ibm-aix* } }
 
 // Copyright (C) 2021-2023 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_multiset/96088.cc b/libstdc++-v3/testsuite/23_containers/unordered_multiset/96088.cc
index d50435aa7a2..838ce8d5bc5 100644
--- a/libstdc++-v3/testsuite/23_containers/unordered_multiset/96088.cc
+++ b/libstdc++-v3/testsuite/23_containers/unordered_multiset/96088.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++17 } }
 // { dg-require-effective-target std_allocator_new }
+// { dg-xfail-run-if "AIX operator new" { powerpc-ibm-aix* } }
 
 // Copyright (C) 2021-2023 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_set/96088.cc b/libstdc++-v3/testsuite/23_containers/unordered_set/96088.cc
index 05a5dc07f62..0f7dce2b38c 100644
--- a/libstdc++-v3/testsuite/23_containers/unordered_set/96088.cc
+++ b/libstdc++-v3/testsuite/23_containers/unordered_set/96088.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++17 } }
 // { dg-require-effective-target std_allocator_new }
+// { dg-xfail-run-if "AIX operator new" { powerpc-ibm-aix* } }
 
 // Copyright (C) 2021-2023 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/experimental/synchronized_value.cc b/libstdc++-v3/testsuite/experimental/synchronized_value.cc
index 8e8134699a2..a7e556c14ea 100644
--- a/libstdc++-v3/testsuite/experimental/synchronized_value.cc
+++ b/libstdc++-v3/testsuite/experimental/synchronized_value.cc
@@ -1,4 +1,6 @@
 // { dg-do run { target c++17 } }
+// { dg-additional-options "-pthread" { target pthread } }
+// { dg-require-gthreads "" }
 
 #include <experimental/synchronized_value>
 #include <testsuite_hooks.h>
