# Strange bug(Segmentation fault: 11) solely existed in julia v1.0

**URL:** <https://discourse.julialang.org/t/strange-bug-segmentation-fault-11-solely-existed-in-julia-v1-0/21392>\
**Category:** General Usage\
**Tags:** bug\
**Created:** [March 2, 2019, 2:36pm UTC](https://discourse.julialang.org/t/strange-bug-segmentation-fault-11-solely-existed-in-julia-v1-0/21392 "2019-03-02T14:36:30Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![thautwarm](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/thautwarm/32/37760_2.png) [@thautwarm](https://discourse.julialang.org/u/thautwarm)\
**Post date:** [March 2, 2019, 2:36pm UTC](https://discourse.julialang.org/t/strange-bug-segmentation-fault-11-solely-existed-in-julia-v1-0/21392/1 "2019-03-02T14:36:30Z")

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Firstly, the codes run well in v1.1 and nightly version.

When it comes to CI in v1.0, there is a strange phenomenon:

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>
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* * *

It firstly appeared when a project requires both DataFrames.jl and MLStyle.jl in Julia v1.0, but at that time I didn’t get a break with this.

Now I’m contributing to Query.jl, taking advantage of MLStyle.jl to largely simplify some ast manipulations: [Simplify macro rewriters and avoid some prospective bugs by thautwarm · Pull Request #238 · queryverse/Query.jl · GitHub](https://github.com/queryverse/Query.jl/pull/238) , thus it has become a severe impedement for it makes tests on v1.0 failed.

The code failed at [https://github.com/thautwarm/MLStyle.jl/blob/master/src/toolz.jl#L23](https://github.com/thautwarm/MLStyle.jl/blob/master/src/toolz.jl#L23) , where I implemented a state monad to make MLStyle’s complex state transformations clean.

Also, this is on the traceback stacks:

```julia
($)(f, a) = f(a)

```

I cannot make sure what happened here, but it seems to be a solid bug in Julia v1.0.

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<div class="post-metadata">

**Author:** ![Tamas\_Papp](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tamas_papp/32/25949_2.png) [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Post date:** [March 4, 2019, 9:25am UTC](https://discourse.julialang.org/t/strange-bug-segmentation-fault-11-solely-existed-in-julia-v1-0/21392/2 "2019-03-04T09:25:43Z")

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You could try a `git bisect` to locate the exact commit that fixed it, ans ask for it to be backported for the next `1.0.x` release.

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<div class="post-metadata">

**Author:** ![thautwarm](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/thautwarm/32/37760_2.png) [@thautwarm](https://discourse.julialang.org/u/thautwarm)\
**Post date:** [March 4, 2019, 9:51am UTC](https://discourse.julialang.org/t/strange-bug-segmentation-fault-11-solely-existed-in-julia-v1-0/21392/3 "2019-03-04T09:51:41Z")

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Okay, I’ll have a try in this week.