Index: test/support/archetypes.hpp
===================================================================
--- test/support/archetypes.hpp
+++ test/support/archetypes.hpp
@@ -5,6 +5,7 @@
 #include <cassert>
 
 #include "test_macros.h"
+#include "test_workarounds.h"
 
 #if TEST_STD_VER >= 11
 
@@ -14,7 +15,9 @@
 struct DepType : T {};
 
 struct NullBase {
+#ifndef TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
 protected:
+#endif // !TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
   NullBase() = default;
   NullBase(NullBase const&) = default;
   NullBase& operator=(NullBase const&) = default;
@@ -81,7 +84,9 @@
       ++assigned; ++value_assigned;
       return *this;
     }
+#ifndef TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
 protected:
+#endif // !TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
     ~TestBase() {
       assert(value != -999); assert(alive > 0);
       --alive; ++destroyed; value = -999;
@@ -144,7 +149,9 @@
     }
     //~ValueBase() { assert(value != -999); value = -999; }
     int value;
+#ifndef TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
 protected:
+#endif // !TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
     constexpr static int check_value(int const& val) {
 #if TEST_STD_VER < 14
       return val == -1 || val == 999 ? (TEST_THROW(42), 0) : val;
@@ -197,7 +204,9 @@
     template <bool Dummy = true, typename std::enable_if<Dummy && !Explicit, bool>::type = true>
     constexpr TrivialValueBase(std::initializer_list<int>& il, int = 0) : value(static_cast<int>(il.size())) {}
     int value;
+#ifndef TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
 protected:
+#endif // !TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
     constexpr TrivialValueBase() noexcept : value(0) {}
 };
 
Index: test/support/archetypes.ipp
===================================================================
--- test/support/archetypes.ipp
+++ test/support/archetypes.ipp
@@ -6,7 +6,11 @@
 #define DEFINE_EXPLICIT
 #endif
 #ifndef DEFINE_CONSTEXPR
+#ifdef TEST_WORKAROUND_EDG_EXPLICIT_CONSTEXPR
+#define DEFINE_CONSTEXPR
+#else // TEST_WORKAROUND_EDG_EXPLICIT_CONSTEXPR
 #define DEFINE_CONSTEXPR constexpr
+#endif // TEST_WORKAROUND_EDG_EXPLICIT_CONSTEXPR
 #endif
 #ifndef DEFINE_ASSIGN_CONSTEXPR
 #if TEST_STD_VER >= 14
Index: test/support/msvc_stdlib_force_include.hpp
===================================================================
--- test/support/msvc_stdlib_force_include.hpp
+++ test/support/msvc_stdlib_force_include.hpp
@@ -13,11 +13,13 @@
 // This header is force-included when running the libc++ tests against the
 // MSVC standard library.
 
-// Silence warnings about CRT machinery.
-#define _CRT_SECURE_NO_WARNINGS
+#ifndef _LIBCXX_IN_DEVCRT
+    // Silence warnings about CRT machinery.
+    #define _CRT_SECURE_NO_WARNINGS
 
-// Avoid assertion dialogs.
-#define _CRT_SECURE_INVALID_PARAMETER(EXPR) ::abort()
+    // Avoid assertion dialogs.
+    #define _CRT_SECURE_INVALID_PARAMETER(EXPR) ::abort()
+#endif // _LIBCXX_IN_DEVCRT
 
 #include <crtdbg.h>
 #include <stdlib.h>
@@ -31,6 +33,7 @@
     #define _MSVC_STL_VER 42
 #endif
 
+#ifndef _LIBCXX_IN_DEVCRT
 struct AssertionDialogAvoider {
     AssertionDialogAvoider() {
         _CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_FILE);
@@ -42,6 +45,7 @@
 };
 
 const AssertionDialogAvoider assertion_dialog_avoider{};
+#endif // _LIBCXX_IN_DEVCRT
 
 // MSVC frontend only configurations
 #if !defined(__clang__)
@@ -69,15 +73,17 @@
 // MSVC has quick_exit() and at_quick_exit().
 #define _LIBCPP_HAS_QUICK_EXIT
 
-// atomic_is_lock_free.pass.cpp needs this VS 2015 Update 2 fix.
-#define _ENABLE_ATOMIC_ALIGNMENT_FIX
+#ifndef _LIBCXX_IN_DEVCRT
+    // atomic_is_lock_free.pass.cpp needs this VS 2015 Update 2 fix.
+    #define _ENABLE_ATOMIC_ALIGNMENT_FIX
 
-// Enable features that /std:c++latest removes by default.
-#define _HAS_AUTO_PTR_ETC          1
-#define _HAS_FUNCTION_ASSIGN       1
-#define _HAS_OLD_IOSTREAMS_MEMBERS 1
+    // Enable features that /std:c++latest removes by default.
+    #define _HAS_AUTO_PTR_ETC          1
+    #define _HAS_FUNCTION_ASSIGN       1
+    #define _HAS_OLD_IOSTREAMS_MEMBERS 1
 
-// Silence warnings about raw pointers and other unchecked iterators.
-#define _SCL_SECURE_NO_WARNINGS
+    // Silence warnings about raw pointers and other unchecked iterators.
+    #define _SCL_SECURE_NO_WARNINGS
+#endif // _LIBCXX_IN_DEVCRT
 
 #endif // SUPPORT_MSVC_STDLIB_FORCE_INCLUDE_HPP
Index: test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp
===================================================================
--- /dev/null
+++ test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03
+
+// Verify TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK.
+
+#include <type_traits>
+
+#include "test_workarounds.h"
+
+struct X {
+    X(int) {}
+
+    X(X&&) = default;
+    X& operator=(X&&) = default;
+
+private:
+    X(const X&) = default;
+    X& operator=(const X&) = default;
+};
+
+void PushFront(X&&) {}
+
+template<class T = int>
+auto test(int) -> decltype(PushFront(std::declval<T>()), std::true_type{});
+auto test(long) -> std::false_type;
+
+int main() {
+#if defined(TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK)
+    static_assert(!decltype(test(0))::value, "");
+#else
+    static_assert(decltype(test(0))::value, "");
+#endif
+}
Index: test/support/test_macros.h
===================================================================
--- test/support/test_macros.h
+++ test/support/test_macros.h
@@ -52,10 +52,12 @@
 #define TEST_HAS_BUILTIN_IDENTIFIER(X) 0
 #endif
 
-#if defined(__clang__)
-#define TEST_COMPILER_CLANG
+#if defined(__EDG__)
+# define TEST_COMPILER_EDG
+#elif defined(__clang__)
+# define TEST_COMPILER_CLANG
 # if defined(__apple_build_version__)
-#   define TEST_COMPILER_APPLE_CLANG
+#  define TEST_COMPILER_APPLE_CLANG
 # endif
 #elif defined(_MSC_VER)
 # define TEST_COMPILER_C1XX
Index: test/support/test_workarounds.h
===================================================================
--- test/support/test_workarounds.h
+++ test/support/test_workarounds.h
@@ -13,9 +13,16 @@
 
 #include "test_macros.h"
 
+#if defined(TEST_COMPILER_EDG)
+# define TEST_WORKAROUND_EDG_EXPLICIT_CONSTEXPR
+#endif
+
 #if defined(TEST_COMPILER_C1XX)
 # define TEST_WORKAROUND_C1XX_BROKEN_NULLPTR_CONVERSION_OPERATOR
 # define TEST_WORKAROUND_C1XX_BROKEN_IS_TRIVIALLY_COPYABLE
+# ifndef _MSC_EXTENSIONS
+#  define TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK
+# endif
 #endif
 
 #endif // SUPPORT_TEST_WORKAROUNDS_H