# Create uninitialised mutable struct

**URL:** <https://discourse.julialang.org/t/create-uninitialised-mutable-struct/81913>\
**Category:** General Usage\
**Created:** [May 30, 2022, 12:15pm UTC](https://discourse.julialang.org/t/create-uninitialised-mutable-struct/81913 "2022-05-30T12:15:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![andrew\_s](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@andrew\_s](https://discourse.julialang.org/u/andrew_s)\
**Post date:** [May 30, 2022, 12:15pm UTC](https://discourse.julialang.org/t/create-uninitialised-mutable-struct/81913/1 "2022-05-30T12:15:15Z")

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I have a mutable struct, E.g.

```julia
mutable struct MyExampleStruct
	a::Cdouble
	b::Cdouble
end

```

which I wish to create with uninitialised fields. I don’t want to use an inner constructor to achieve this. This will be passed to Fortran code using `ccall`. Does anyone know how I can accomplish this? Thanks.

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<div class="post-metadata">

**Author:** ![cjdoris](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cjdoris/32/213133_2.png) [@cjdoris](https://discourse.julialang.org/u/cjdoris)\
**Post date:** [May 30, 2022, 12:23pm UTC](https://discourse.julialang.org/t/create-uninitialised-mutable-struct/81913/2 "2022-05-30T12:23:25Z")

</div>

> [@andrew\_s](#):
>
> I don’t want to use an inner constructor to achieve this.

Why not? How it is constructed is nothing to do with Fortran.