diff --git a/.gitignore b/.gitignore
index e38d506..7b550f2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 /cmake-build-debug/
+/cmake-build-debug-windows/
 /cmake-build-debug-coverage/
 /cmake-build-release/
 /build-release-windows/
diff --git a/src/Memory/__BorrowedPtr.hpp b/src/Memory/__BorrowedPtr.hpp
index 08124cf..8881526 100644
--- a/src/Memory/__BorrowedPtr.hpp
+++ b/src/Memory/__BorrowedPtr.hpp
@@ -2,6 +2,7 @@
 #define ARBUTILS___BORROWEDPTR_HPP
 
 #include "../Ensure.hpp"
+#include <cstddef>
 
 namespace ArbUt {
     /// @brief A borrowed pointer is used to indicate a pointer that is not owned by its holder. As with all Arbutils
@@ -22,7 +23,9 @@ namespace ArbUt {
         /// @brief Initialise a BorrowedPtr with a std unique_ptr.
         inline BorrowedPtr<T>(const std::unique_ptr<T>& other) : _raw(other.get()){};
 
+#if !WINDOWS // This doesn't work on mingw-w64 for some reason
         BorrowedPtr<T>(std::nullptr_t) = delete;
+#endif
 
         ~BorrowedPtr() noexcept = default;
 
diff --git a/src/Memory/__ScopedPtr.hpp b/src/Memory/__ScopedPtr.hpp
index 589b6bc..68a3c16 100644
--- a/src/Memory/__ScopedPtr.hpp
+++ b/src/Memory/__ScopedPtr.hpp
@@ -20,7 +20,9 @@ namespace ArbUt {
         /// @brief Initialise a ScopedPtr with a std unique_ptr.
         inline ScopedPtr<T>(const std::unique_ptr<T>& other) : _raw(other.get()){};
 
+#if !WINDOWS // This doesn't work on mingw-w64 for some reason
         ScopedPtr<T>(std::nullptr_t) = delete;
+#endif
 
         ~ScopedPtr() noexcept { delete _raw; }
 
diff --git a/src/Memory/__UniquePtr.hpp b/src/Memory/__UniquePtr.hpp
index b114783..1ce4411 100644
--- a/src/Memory/__UniquePtr.hpp
+++ b/src/Memory/__UniquePtr.hpp
@@ -22,7 +22,9 @@ namespace ArbUt {
         /// @brief Initialise a UniquePtr with a std unique_ptr.
         inline UniquePtr<T>(const std::unique_ptr<T>& other) : _raw(other.get()){};
 
+#if !WINDOWS // This doesn't work on mingw-w64 for some reason
         UniquePtr<T>(std::nullptr_t) = delete;
+#endif
 
         ~UniquePtr() noexcept { delete _raw; }