diff --git a/libcxxabi/src/stdlib_new_delete.cpp b/libcxxabi/src/stdlib_new_delete.cpp
--- a/libcxxabi/src/stdlib_new_delete.cpp
+++ b/libcxxabi/src/stdlib_new_delete.cpp
@@ -12,6 +12,7 @@
 #include <__memory/aligned_alloc.h>
 #include <cstdlib>
 #include <new>
+#include <__utility/unreachable.h>
 
 #if !defined(_THROW_BAD_ALLOC) || !defined(_LIBCXXABI_WEAK)
 #error The _THROW_BAD_ALLOC and _LIBCXXABI_WEAK libc++ macros must \
@@ -39,28 +40,26 @@
 #ifndef _LIBCXXABI_NO_EXCEPTIONS
             throw std::bad_alloc();
 #else
-            break;
+            std::__libcpp_unreachable();
 #endif
     }
     return p;
 }
 
 _LIBCXXABI_WEAK
-void*
-operator new(size_t size, const std::nothrow_t&) noexcept
-{
-    void* p = nullptr;
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    try
-    {
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-        p = ::operator new(size);
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    }
-    catch (...)
-    {
+void* operator new(size_t size, const std::nothrow_t&) noexcept {
+    if (size == 0)
+        size = 1;
+    void* p;
+    while ((p = ::malloc(size)) == nullptr) {
+        // If malloc fails and there is a new_handler,
+        // call it to try free up memory.
+        std::new_handler nh = std::get_new_handler();
+        if (nh)
+            nh();
+        else
+            break;
     }
-#endif // _LIBCXXABI_NO_EXCEPTIONS
     return p;
 }
 
@@ -72,23 +71,7 @@
 }
 
 _LIBCXXABI_WEAK
-void*
-operator new[](size_t size, const std::nothrow_t&) noexcept
-{
-    void* p = nullptr;
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    try
-    {
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-        p = ::operator new[](size);
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    }
-    catch (...)
-    {
-    }
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-    return p;
-}
+void* operator new[](size_t size, const std::nothrow_t& nothrow) noexcept { return ::operator new(size, nothrow); }
 
 _LIBCXXABI_WEAK
 void
@@ -159,7 +142,7 @@
 #ifndef _LIBCXXABI_NO_EXCEPTIONS
             throw std::bad_alloc();
 #else
-            break;
+            std::__libcpp_unreachable();
 #endif
         }
     }
@@ -170,18 +153,26 @@
 void*
 operator new(size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept
 {
-    void* p = nullptr;
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    try
-    {
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-        p = ::operator new(size, alignment);
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    }
-    catch (...)
-    {
+    if (size == 0)
+        size = 1;
+    if (static_cast<size_t>(alignment) < sizeof(void*))
+        alignment = std::align_val_t(sizeof(void*));
+
+    // Try allocating memory. If allocation fails and there is a new_handler,
+    // call it to try free up memory, and try again until it succeeds, or until
+    // the new_handler decides to terminate.
+    //
+    // If allocation fails and there is no new_handler, we throw bad_alloc
+    // (or return nullptr if exceptions are disabled).
+    void* p;
+    while ((p = std::__libcpp_aligned_alloc(static_cast<size_t>(alignment), size)) == nullptr) {
+        std::new_handler nh = std::get_new_handler();
+        if (nh)
+            nh();
+        else {
+            break;
+        }
     }
-#endif // _LIBCXXABI_NO_EXCEPTIONS
     return p;
 }
 
@@ -193,22 +184,8 @@
 }
 
 _LIBCXXABI_WEAK
-void*
-operator new[](size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept
-{
-    void* p = nullptr;
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    try
-    {
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-        p = ::operator new[](size, alignment);
-#ifndef _LIBCXXABI_NO_EXCEPTIONS
-    }
-    catch (...)
-    {
-    }
-#endif // _LIBCXXABI_NO_EXCEPTIONS
-    return p;
+void* operator new[](size_t size, std::align_val_t alignment, const std::nothrow_t& nothrow) noexcept {
+    return ::operator new(size, alignment, nothrow);
 }
 
 _LIBCXXABI_WEAK