crashes in profiler

[tmptrash]

Hello everybody,

Yesterday i tried to use embedded profile (@profile macro) and ProfileView package to measure performance. I found it impossible, because of stable crashes (at least on my machine). A have two types of them. First is reproducible with this code:

type T
  f::Function
  inF::Function
  t::Task
  T(f) = new(f)
end

function main()
    amount = 2
    tasks  = T[]
    for i = 1:amount
      t     = T(function(t) function() while true produce(); t.inF() end end end)
      t.inF = function() produce(); produce(); produce() end
      t.t   = Task(t.f(t))
      push!(tasks, t)
    end

    while true
      for i = 1:amount
        t = tasks[i]
        if rand(1:5) == 3
          t.inF = eval(:(function() produce(); produce(); produce() end))
        end
        consume(t.t)
      end
    end
end

@profile main()

This is an error, which i get with code above:

>julia tmp\\consume.jl
failed to get context from main thread. aborting profiling.

Second one is only reproducible on my project and it looks really asynchronous. I added special code, which produces the bug, but it depends on my sources. So, you have to clone my repo first ;) You may run it like this:

>julia --color=yes -q -i src/AppManagerBug.jl recover quiet

Code above produces this error:

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 0x7ffe99794a71 -- RtlVirtualUnwind at C:\WINDOWS\SYSTEM32\ntdll.dll (unknown line)
RtlVirtualUnwind at C:\WINDOWS\SYSTEM32\ntdll.dll (unknown line)
RtlVirtualUnwind at C:\WINDOWS\system32\KERNEL32.DLL (unknown line)
rec_backtrace_ctx at c:\Users\User\AppData\Local\Julia-0.4.6\bin\libjulia.dll (unknown line)
jl_typeof at c:\Users\User\AppData\Local\Julia-0.4.6\bin\libjulia.dll (unknown line)
BaseThreadInitThunk at C:\WINDOWS\system32\KERNEL32.DLL (unknown line)
RtlUserThreadStart at C:\WINDOWS\SYSTEM32\ntdll.dll (unknown line)

[tmptrash]

No thoughts about this?

[vtjnash]

I can say for certain the backtrack will be better in 0.5 :P

I suspect it's failing if it gets stopped in the setjmp code. Quick fix hack might be to just set/clear jl_in_stackwalk in ctx_switch (and start_task)

[tmptrash]

Better, or fixed? :)

[vtjnash]

The backtrace should contain the actual function names instead of random ones, but with an unchanged probability of segfaulting instead.

[tmptrash]

So, in this case this is actual issue. To be onest it works 2 times from 10 on my pc :(

If you need more details, i may provide them ;)

[KristofferC]

Please comment if this still happens.

[pfitzseb]

This seems similar:

               _
   _       _ _(_)_     |  A fresh approach to technical computing
  (_)     | (_) (_)    |  Documentation: https://docs.julialang.org
   _ _   _| |_  __ _   |  Type "?help" for help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 0.7.0-DEV.4690 (2018-03-23 22:25 UTC)
 _/ |\__'_|_|_|\__'_|  |  Commit 78c7d87369* (23 days old master)
|__/                   |  x86_64-w64-mingw32

julia> using Profile

julia> @profile gcd(BigInt(2)^165622200+2, BigInt(2)^14404211+5)

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 0x6b5dd650 -- jl_unw_step at /home/Administrator/buildbot/worker/package_win64/build/src\stackwalk.c:326 [inlined]
jl_unw_stepn at /home/Administrator/buildbot/worker/package_win64/build/src\stackwalk.c:51 [inlined]
rec_backtrace_ctx at /home/Administrator/buildbot/worker/package_win64/build/src\stackwalk.c:86
in expression starting at no file:0

[BioTurboNick]

Just came across this researching an EXCEPTION_ACCESS_VIOLATION in 1.1. Just noting for the record that 1.3.0-rc3 has fixed this.

[joseortiz3]

I also found this in Julia 1.2.0. Will move to 1.3.0 now per @BioTurboNick's recommendation

               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.2.0 (2019-08-20)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using Profile

julia> @profile gcd(BigInt(2)^165622200+2, BigInt(2)^14404211+5)

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 0x6b5e709d -- rec_backtrace_ctx at /home/Administrator/buildbot/worker/package_win64/build/src/home/Administrator/buildbot/worker/package_win64/build/src\stackwalk.c:372
in expression starting at none:0

That's weird, 1.3.0 appears to work with the above gcd example, but in my other code I am still getting an EXCEPTION_ACCESS_VIOLATION.