Fix segfault on complex pointer formatting (#285)

Source/GmmLib/Utility/GmmLog/spdlog/details/format.h

diff --git a/Source/GmmLib/Utility/GmmLog/spdlog/details/format.h b/Source/GmmLib/Utility/GmmLog/spdlog/details/format.h
index 34551f7..e849181 100644
--- a/Source/GmmLib/Utility/GmmLog/spdlog/details/format.h
+++ b/Source/GmmLib/Utility/GmmLog/spdlog/details/format.h
@@ -3084,14 +3084,15 @@
             CharPtr p = grow_buffer(fill_size);
             std::uninitialized_fill(p, p + fill_size, fill);
         }
-        CharPtr result = prepare_int_buffer(
-                             num_digits, subspec, prefix, prefix_size);
+        std::ptrdiff_t offset = get(prepare_int_buffer(
+                                num_digits, subspec, prefix, prefix_size)) -
+                                &buffer_[0];
         if (align == ALIGN_LEFT)
         {
             CharPtr p = grow_buffer(fill_size);
             std::uninitialized_fill(p, p + fill_size, fill);
         }
-        return result;
+        return internal::make_ptr(&buffer_[0], buffer_.size()) + offset;
     }
     unsigned size = prefix_size + num_digits;
     if (width <= size)