# Compiling sys.o: Segmentation fault in expression starting at none:0

**URL:** https://discourse.julialang.org/t/compiling-sys-o-segmentation-fault-in-expression-starting-at-none-0/41838
**Category:** New to Julia
**Created:** [June 22, 2020, 5:57am UTC](https://discourse.julialang.org/t/compiling-sys-o-segmentation-fault-in-expression-starting-at-none-0/41838 "2020-06-22T05:57:38Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![German\_Salazar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/german_salazar/32/11994_2.png) [@German\_Salazar](https://discourse.julialang.org/u/German_Salazar)
#### Post date: [June 22, 2020, 5:57am UTC](https://discourse.julialang.org/t/compiling-sys-o-segmentation-fault-in-expression-starting-at-none-0/41838/1 "2020-06-22T05:57:38Z")

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Say, I was following the instructions from the PackageCompiler on how to manually compile an app; but, I am getting an error right away with no hint as to what’s wrong:

```bash
julia --startup-file=no -J"/path/to/julia/1.4.2/lib/julia/sys.so" --output-o sys.o custom_sysimage.jl

signal (11): Segmentation fault
in expression starting at none:0
uv_write2 at /workspace/srcdir/libuv/src/unix/stream.c:1397
.
.
.

```

Any idea what the problem could be?

I am in CentOS 7 and just downloaded Julia 1.4.2

---

<div class="post-metadata">

### Author: ![German\_Salazar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/german_salazar/32/11994_2.png) [@German\_Salazar](https://discourse.julialang.org/u/German_Salazar)
#### Post date: [June 24, 2020, 2:47am UTC](https://discourse.julialang.org/t/compiling-sys-o-segmentation-fault-in-expression-starting-at-none-0/41838/2 "2020-06-24T02:47:25Z")

</div>

Never mind…I figured it out; after carefully, manually, running PackageCompiler with additional debug statement, I notice that something was missing inside the custom\_sysimage.jl file.