--- boost_1_69_0/boost/format/alt_sstream_impl.hpp~	2020-03-30 15:20:18.565658757 +0100
+++ boost_1_69_0/boost/format/alt_sstream_impl.hpp	2020-03-30 15:20:33.768636162 +0100
@@ -40,8 +40,11 @@
 #ifdef _RWSTD_NO_CLASS_PARTIAL_SPEC
                 void *vd_ptr = alloc_.allocate(sz, is_allocated_? eback() : 0);
                 Ch *new_ptr = static_cast<Ch *>(vd_ptr);
-#else
+#elif defined BOOST_NO_CXX11_ALLOCATOR
                 Ch *new_ptr = alloc_.allocate(sz, is_allocated_? eback() : 0);
+#else
+                Ch *new_ptr = std::allocator_traits<compat_allocator_type>::allocate(alloc_,
+                    sz, is_allocated_? eback() : 0);
 #endif
                 // if this didnt throw, we're safe, update the buffer
                 dealloc();
@@ -257,8 +260,11 @@
 #ifdef _RWSTD_NO_CLASS_PARTIAL_SPEC
                     void *vdptr = alloc_.allocate(new_size, is_allocated_? oldptr : 0);
                     newptr = static_cast<Ch *>(vdptr);
-#else
+#elif defined BOOST_NO_CXX11_ALLOCATOR
                     newptr = alloc_.allocate(new_size, is_allocated_? oldptr : 0);
+#else
+                    newptr = std::allocator_traits<compat_allocator_type>::allocate(alloc_,
+                        new_size, is_allocated_? oldptr : 0);
 #endif
                 }