diff --git a/libcxx/include/locale b/libcxx/include/locale
--- a/libcxx/include/locale
+++ b/libcxx/include/locale
@@ -1567,7 +1567,7 @@
             __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, (int)__iob.precision(), __v);
         else
             __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, __v);
-        if (__nb == nullptr)
+        if (__nc == -1)
             __throw_bad_alloc();
         __nbh.reset(__nb);
     }
@@ -1618,7 +1618,7 @@
             __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, (int)__iob.precision(), __v);
         else
             __nc = __libcpp_asprintf_l(&__nb, _LIBCPP_GET_C_LOCALE, __fmt, __v);
-        if (__nb == nullptr)
+        if (__nc == -1)
             __throw_bad_alloc();
         __nbh.reset(__nb);
     }
@@ -3399,7 +3399,7 @@
     if (__n > __bs-1)
     {
         __n = static_cast<size_t>(__libcpp_asprintf_l(&__bb, _LIBCPP_GET_C_LOCALE, "%.0Lf", __units));
-        if (__bb == nullptr)
+        if (__n == -1)
             __throw_bad_alloc();
         __hn.reset(__bb);
         __hd.reset((char_type*)malloc(__n * sizeof(char_type)));