# Unsatisfiable requirements for ForwardDiff on Julia 1.0

**URL:** <https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622>\
**Category:** General Usage\
**Created:** [September 6, 2018, 2:24pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622 "2018-09-06T14:24:41Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![ExpandingMan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/expandingman/32/866_2.png) [@ExpandingMan](https://discourse.julialang.org/u/ExpandingMan)\
**Post date:** [September 6, 2018, 2:24pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/1 "2018-09-06T14:24:41Z")

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I am working with version 0.18.2+ of JuMP (JuMP 0.18 compatible with 1.0) and I get the following error when I do `resolve`:

```julia
ERROR: Unsatisfiable requirements detected for package ForwardDiff [f6369f11]:
 ForwardDiff [f6369f11] log:
 ├─possible versions are: [0.0.2-0.0.3, 0.1.0-0.1.8, 0.2.0-0.2.5, 0.3.0-0.3.5, 0.4.0-0.4.2, 0.5.0, 0.6.0, 0.7.0-0.7.5, 0.8.0-0.8.5, 0.9.0] or uninstalled
 ├─restricted to versions 0.5.0-0.8 by JuMP [4076af6c], leaving only versions [0.5.0, 0.6.0, 0.7.0-0.7.5, 0.8.0-0.8.5]
 │ └─JuMP [4076af6c] log:
 │ ├─possible versions are: 0.18.2 or uninstalled
 │ └─JuMP [4076af6c] is fixed to version 0.18.2+
 ├─restricted to versions 0.8.5 by an explicit requirement, leaving only versions 0.8.5
 └─restricted by julia compatibility requirements to versions: [0.1.3-0.1.8, 0.2.0-0.2.5, 0.3.0-0.3.4, 0.9.0] or uninstalled — no versions left

```

I’m pretty stumped here. Is this a bug?

(I see some old, similar issues which I don’t _think_ are related)

The _only_ way I can get this working at all is going into the `JuMP` `REQUIRE` and allowing it to use ForwardDiff 0.9. Obviously that’s not an ideal solution.

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<div class="post-metadata">

**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [September 6, 2018, 2:32pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/2 "2018-09-06T14:32:40Z")

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[add Julia v1.0 upperbound to old ForwardDiff releases by jrevels · Pull Request #17516 · JuliaLang/METADATA.jl · GitHub](https://github.com/JuliaLang/METADATA.jl/pull/17516) perhaps

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<div class="post-metadata">

**Author:** ![ExpandingMan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/expandingman/32/866_2.png) [@ExpandingMan](https://discourse.julialang.org/u/ExpandingMan)\
**Post date:** [September 6, 2018, 2:38pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/3 "2018-09-06T14:38:03Z")

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Hm, so assuming this was fixed in METADATA, how do I resolve? Shouldn’t it work now? The merge happened 20 hours ago.

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**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [September 6, 2018, 2:45pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/4 "2018-09-06T14:45:37Z")

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I meant the opposite, that that PR perhaps caused this 🙂

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<div class="post-metadata">

**Author:** ![ExpandingMan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/expandingman/32/866_2.png) [@ExpandingMan](https://discourse.julialang.org/u/ExpandingMan)\
**Post date:** [September 6, 2018, 2:47pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/5 "2018-09-06T14:47:32Z")

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Oh I see, that was silly of me right, the bounds are like [a, b)?

Yes, if that’s the case than they definitely broke this (whether or not that’s the problem I’m seeing).

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**Author:** ![tshort](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tshort/32/43_2.png) [@tshort](https://discourse.julialang.org/u/tshort)\
**Post date:** [September 6, 2018, 2:57pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/6 "2018-09-06T14:57:04Z")

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The README file for JuMP shows that JuMP v0.18.2 is not compatible with Julia v0.7/1.0.

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<div class="post-metadata">

**Author:** ![ExpandingMan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/expandingman/32/866_2.png) [@ExpandingMan](https://discourse.julialang.org/u/ExpandingMan)\
**Post date:** [September 6, 2018, 2:59pm UTC](https://discourse.julialang.org/t/unsatisfiable-requirements-for-forwarddiff-on-julia-1-0/14622/7 "2018-09-06T14:59:18Z")

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Ok, I’m pretty sure @kristoffer.carlsson is right and that was the issue. I made a [PR](https://github.com/JuliaOpt/JuMP.jl/pull/1457).

> [@tshort](#):
>
> The README file for JuMP shows that JuMP v0.18.2 is not compatible with Julia v0.7/1.0.

Yes I have fixed that 😄. (It’s in the JuMP `release-0.18` branch, but there isn’t an official 0.18.3 yet.)