# EXCEPTION\_ACCESS\_VIOLATION in windows64

**URL:** <https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660>\
**Category:** Internals & Design\
**Tags:** bug\
**Created:** [May 27, 2019, 8:25pm UTC](https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660 "2019-05-27T20:25:12Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![s-baumann](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/s-baumann/32/5843_2.png) [@s-baumann](https://discourse.julialang.org/u/s-baumann)\
**Post date:** [May 27, 2019, 8:25pm UTC](https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660/1 "2019-05-27T20:25:12Z")

</div>

I have a bug to report in Version 1.1.0 (2019-01-21) on 64 bit Windows.

I get Julia crashing and the following bug report a bunch of times

> Please submit a bug report with steps to reproduce this fault, and any error messages that follow (in their entirety). Thanks.  
> Exception: EXCEPTION\_ACCESS\_VIOLATION at 0x7ffe39eba1b9 –

This happens whenever I run the code (this is the MWE):

```julia
Convergence = 2.3728475043304586e13
ReportingSigFig = UInt64(10)
lpad(round(Convergence, digits=ReportingSigFig),ReportingSigFig+3)

```

But the following two version run as expected without error:

```julia
# A smaller number to round is fine
Convergence = 2.3728475043304586
ReportingSigFig = UInt64(10)
lpad(round(Convergence, digits=ReportingSigFig),ReportingSigFig+3)

```

```julia
# Using Signed Ints also makes it work
Convergence = 2.3728475043304586e13
ReportingSigFig = Int64(10)
lpad(round(Convergence, digits=ReportingSigFig),ReportingSigFig+3)

```

---

<div class="post-metadata">

**Author:** ![s-baumann](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/s-baumann/32/5843_2.png) [@s-baumann](https://discourse.julialang.org/u/s-baumann)\
**Post date:** [May 27, 2019, 8:42pm UTC](https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660/2 "2019-05-27T20:42:35Z")

</div>

The MWE can be shortened to:

```julia
Convergence = 2.3728475043304586e13
lpad(Convergence,UInt64(13))

```

with the error still occuring

---

<div class="post-metadata">

**Author:** ![c42f](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/c42f/32/52842_2.png) [@c42f](https://discourse.julialang.org/u/c42f)\
**Post date:** [May 27, 2019, 11:18pm UTC](https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660/3 "2019-05-27T23:18:04Z")

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Thanks, I can reproduce on the official linux build with julia 1.1

```julia
julia> lpad("xx", UInt64(1), " ")

signal (11): Segmentation fault
in expression starting at no file:0
Segmentation fault (core dumped)

```

Reported on github: [https://github.com/JuliaLang/julia/issues/32160](https://github.com/JuliaLang/julia/issues/32160)

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<div class="post-metadata">

**Author:** ![c42f](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/c42f/32/52842_2.png) [@c42f](https://discourse.julialang.org/u/c42f)\
**Post date:** [May 28, 2019, 5:33am UTC](https://discourse.julialang.org/t/exception-access-violation-in-windows64/24660/4 "2019-05-28T05:33:10Z")

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Should be fixed in: [Fix unsigned wrap around in lpad/rpad/string allocation by c42f · Pull Request #32161 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/32161)