Index: include/stdexcept
===================================================================
--- include/stdexcept
+++ include/stdexcept
@@ -54,6 +54,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
 class _LIBCPP_HIDDEN __libcpp_refstring
 {
     const char* __imp_;
@@ -67,6 +68,7 @@
 
     const char* c_str() const _NOEXCEPT {return __imp_;}
 };
+#endif // !_LIBCPP_ABI_VCRUNTIME
 
 _LIBCPP_END_NAMESPACE_STD
 
@@ -76,6 +78,7 @@
 class _LIBCPP_EXCEPTION_ABI logic_error
     : public exception
 {
+#ifndef _LIBCPP_ABI_VCRUNTIME
 private:
     _VSTD::__libcpp_refstring __imp_;
 public:
@@ -88,11 +91,17 @@
     virtual ~logic_error() _NOEXCEPT;
 
     virtual const char* what() const _NOEXCEPT;
+#else
+public:
+    explicit logic_error(const _VSTD::string&); // Symbol uses versioned std::string
+    _LIBCPP_INLINE_VISIBILITY explicit logic_error(const char* __s) : exception(__s) {}
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI runtime_error
     : public exception
 {
+#ifndef _LIBCPP_ABI_VCRUNTIME
 private:
     _VSTD::__libcpp_refstring __imp_;
 public:
@@ -105,6 +114,11 @@
     virtual ~runtime_error() _NOEXCEPT;
 
     virtual const char* what() const _NOEXCEPT;
+#else
+public:
+   explicit runtime_error(const _VSTD::string&); // Symbol uses versioned std::string
+   _LIBCPP_INLINE_VISIBILITY explicit runtime_error(const char* __s) : exception(__s) {}
+#endif // _LIBCPP_ABI_VCRUNTIME
 };
 
 class _LIBCPP_EXCEPTION_ABI domain_error
@@ -114,7 +128,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit domain_error(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit domain_error(const char* __s)   : logic_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~domain_error() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI invalid_argument
@@ -124,7 +140,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit invalid_argument(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit invalid_argument(const char* __s)   : logic_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~invalid_argument() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI length_error
@@ -133,8 +151,9 @@
 public:
     _LIBCPP_INLINE_VISIBILITY explicit length_error(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit length_error(const char* __s)   : logic_error(__s) {}
-
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~length_error() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI out_of_range
@@ -144,7 +163,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit out_of_range(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit out_of_range(const char* __s)   : logic_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~out_of_range() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI range_error
@@ -154,7 +175,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit range_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit range_error(const char* __s)   : runtime_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~range_error() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI overflow_error
@@ -164,7 +187,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit overflow_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit overflow_error(const char* __s)   : runtime_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~overflow_error() _NOEXCEPT;
+#endif
 };
 
 class _LIBCPP_EXCEPTION_ABI underflow_error
@@ -174,7 +199,9 @@
     _LIBCPP_INLINE_VISIBILITY explicit underflow_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit underflow_error(const char* __s)   : runtime_error(__s) {}
 
+#ifndef _LIBCPP_ABI_VCRUNTIME
     virtual ~underflow_error() _NOEXCEPT;
+#endif
 };
 
 }  // std
Index: src/stdexcept.cpp
===================================================================
--- src/stdexcept.cpp
+++ src/stdexcept.cpp
@@ -10,87 +10,9 @@
 #include "new"
 #include "string"
 #include "system_error"
-#include "include/refstring.h"
 
-/* For _LIBCPPABI_VERSION */
-#if !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) && \
-    (defined(LIBCXX_BUILDING_LIBCXXABI) || defined(__APPLE__) || defined(LIBCXXRT))
-#include <cxxabi.h>
+#ifdef _LIBCPP_ABI_VCRUNTIME
+#include "support/runtime/stdexcept_vcruntime.ipp"
+#else
+#include "support/runtime/stdexcept_default.ipp"
 #endif
-
-static_assert(sizeof(std::__libcpp_refstring) == sizeof(const char *), "");
-
-
-namespace std  // purposefully not using versioning namespace
-{
-
-logic_error::logic_error(const string& msg) : __imp_(msg.c_str())
-{
-}
-
-logic_error::logic_error(const char* msg) : __imp_(msg)
-{
-}
-
-logic_error::logic_error(const logic_error& le) _NOEXCEPT : __imp_(le.__imp_)
-{
-}
-
-logic_error&
-logic_error::operator=(const logic_error& le) _NOEXCEPT
-{
-    __imp_ = le.__imp_;
-    return *this;
-}
-
-runtime_error::runtime_error(const string& msg) : __imp_(msg.c_str())
-{
-}
-
-runtime_error::runtime_error(const char* msg) : __imp_(msg)
-{
-}
-
-runtime_error::runtime_error(const runtime_error& le) _NOEXCEPT
-  : __imp_(le.__imp_)
-{
-}
-
-runtime_error&
-runtime_error::operator=(const runtime_error& le) _NOEXCEPT
-{
-    __imp_ = le.__imp_;
-    return *this;
-}
-
-#if !defined(_LIBCPPABI_VERSION) && !defined(LIBSTDCXX)
-
-const char*
-logic_error::what() const _NOEXCEPT
-{
-    return __imp_.c_str();
-}
-
-const char*
-runtime_error::what() const _NOEXCEPT
-{
-    return __imp_.c_str();
-}
-
-#if !defined(_LIBCPP_ABI_VCRUNTIME)
-
-logic_error::~logic_error() _NOEXCEPT {}
-domain_error::~domain_error() _NOEXCEPT {}
-invalid_argument::~invalid_argument() _NOEXCEPT {}
-length_error::~length_error() _NOEXCEPT {}
-out_of_range::~out_of_range() _NOEXCEPT {}
-
-runtime_error::~runtime_error() _NOEXCEPT {}
-range_error::~range_error() _NOEXCEPT {}
-overflow_error::~overflow_error() _NOEXCEPT {}
-underflow_error::~underflow_error() _NOEXCEPT {}
-
-#endif
-#endif
-
-}  // std
Index: src/support/runtime/stdexcept_default.ipp
===================================================================
--- /dev/null
+++ src/support/runtime/stdexcept_default.ipp
@@ -0,0 +1,88 @@
+//===--------------------- stdexcept_default.ipp --------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "../../include/refstring.h"
+
+/* For _LIBCPPABI_VERSION */
+#if !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) && \
+    (defined(LIBCXX_BUILDING_LIBCXXABI) || defined(__APPLE__) || defined(LIBCXXRT))
+#include <cxxabi.h>
+#endif
+
+static_assert(sizeof(std::__libcpp_refstring) == sizeof(const char *), "");
+
+namespace std  // purposefully not using versioning namespace
+{
+
+logic_error::logic_error(const string& msg) : __imp_(msg.c_str())
+{
+}
+
+logic_error::logic_error(const char* msg) : __imp_(msg)
+{
+}
+
+logic_error::logic_error(const logic_error& le) _NOEXCEPT : __imp_(le.__imp_)
+{
+}
+
+logic_error&
+logic_error::operator=(const logic_error& le) _NOEXCEPT
+{
+__imp_ = le.__imp_;
+return *this;
+}
+
+runtime_error::runtime_error(const string& msg) : __imp_(msg.c_str())
+{
+}
+
+runtime_error::runtime_error(const char* msg) : __imp_(msg)
+{
+}
+
+runtime_error::runtime_error(const runtime_error& le) _NOEXCEPT
+: __imp_(le.__imp_)
+{
+}
+
+runtime_error&
+runtime_error::operator=(const runtime_error& le) _NOEXCEPT
+{
+__imp_ = le.__imp_;
+return *this;
+}
+
+#if !defined(_LIBCPPABI_VERSION) && !defined(LIBSTDCXX)
+
+const char*
+logic_error::what() const _NOEXCEPT
+{
+return __imp_.c_str();
+}
+
+const char*
+runtime_error::what() const _NOEXCEPT
+{
+return __imp_.c_str();
+}
+
+logic_error::~logic_error() _NOEXCEPT {}
+domain_error::~domain_error() _NOEXCEPT {}
+invalid_argument::~invalid_argument() _NOEXCEPT {}
+length_error::~length_error() _NOEXCEPT {}
+out_of_range::~out_of_range() _NOEXCEPT {}
+
+runtime_error::~runtime_error() _NOEXCEPT {}
+range_error::~range_error() _NOEXCEPT {}
+overflow_error::~overflow_error() _NOEXCEPT {}
+underflow_error::~underflow_error() _NOEXCEPT {}
+
+#endif
+
+} // namespace std
Index: src/support/runtime/stdexcept_vcruntime.ipp
===================================================================
--- /dev/null
+++ src/support/runtime/stdexcept_vcruntime.ipp
@@ -0,0 +1,16 @@
+//===------------------- stdexcept_vcruntime.ipp --------------------------===//
+//
+// 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_ABI_VCRUNTIME
+#error This file may only be used when defering to vcruntime
+#endif
+
+namespace std {
+  logic_error::logic_error(std::string const& s) : exception(s.c_str()) {}
+  runtime_error::runtime_error(std::string const& s) : exception(s.c_str()) {}
+}