diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 34
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 38
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 34
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 38
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... fails assertion line 31
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 32
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 36
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 
 // <atomic>
 
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 35
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 //  ... assertion fails line 31
 
 // <atomic>
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 
 // <atomic>
 
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// XFAIL: !non-lockfree-atomics
 
 // <atomic>
 
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.wait/atomic_wait.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.wait/atomic_wait.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.wait/atomic_wait.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.wait/atomic_wait.pass.cpp
@@ -8,6 +8,7 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 // XFAIL: c++03
+// XFAIL: !non-lockfree-atomics
 
 // This test requires the dylib support introduced in D68480,
 // which hasn't shipped yet.
diff --git a/libcxx/utils/libcxx/test/features.py b/libcxx/utils/libcxx/test/features.py
--- a/libcxx/utils/libcxx/test/features.py
+++ b/libcxx/utils/libcxx/test/features.py
@@ -127,6 +127,7 @@
   Feature(name='darwin', when=lambda cfg: '__APPLE__' in compilerMacros(cfg)),
   Feature(name='windows', when=lambda cfg: '_WIN32' in compilerMacros(cfg)),
   Feature(name='linux', when=lambda cfg: '__linux__' in compilerMacros(cfg)),
+  Feature(name='freebsd', when=lambda cfg: '__FreeBSD__' in compilerMacros(cfg)),
   Feature(name='netbsd', when=lambda cfg: '__NetBSD__' in compilerMacros(cfg))
 ]