Merge commit '0f622bd281bd' from llvm.org/main into next

Author: git apple-llvm automerger

libcxx/CMakeLists.txt

@@ -675,8 +675,6 @@ if (LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY AND LIBCXX_ENABLE_SHARED)
 endif()
 
 # Assertion flags =============================================================
-define_if(LIBCXX_ENABLE_ASSERTIONS -UNDEBUG)
-define_if_not(LIBCXX_ENABLE_ASSERTIONS -DNDEBUG)
 define_if(LIBCXX_ENABLE_ASSERTIONS -D_LIBCPP_DEBUG=0)
 define_if(LIBCXX_DEBUG_BUILD -D_DEBUG)
 if (LIBCXX_ENABLE_ASSERTIONS AND NOT LIBCXX_DEBUG_BUILD)

libcxx/benchmarks/algorithms.bench.cpp

@@ -151,7 +151,6 @@ void fillValues(std::vector<std::string>& V, size_t N, Order O) {
 
 template <class T>
 void sortValues(T& V, Order O) {
-  assert(std::is_sorted(V.begin(), V.end()));
   switch (O) {
   case Order::Random: {
     std::random_device R;