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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sat, Sep 21, 2024 at 5:33=E2=80=AFPM Danilo Krummrich = wrote: > @@ -84,11 +92,18 @@ unsafe fn call( > &self, > ptr: Option>, > layout: Layout, > + old_layout: Layout, > flags: Flags, > ) -> Result, AllocError> { > let size =3D aligned_size(layout); > let ptr =3D match ptr { > - Some(ptr) =3D> ptr.as_ptr(), > + Some(ptr) =3D> { > + if old_layout.size() =3D=3D 0 { > + ptr::null() > + } else { > + ptr.as_ptr() > + } > + } This is making Allocator work with zero-sized types, which deviates from std. We should not do that without a reason. What is the reason? Alice