Debugging Plots.jl, TimerOutputs.jl and CSV.jl crashes

[KristofferC]

Tried

julia> using Plots, MagneticReadHead

julia> @time @iron_debug plot(rand(5))
Internal error: encountered unexpected error in runtime:
BoundsError(a=Array{Any, (597,)}[SSAValue(1), SSAValue(2), ....
rec_backtrace at /home/Administrator/buildbot/worker/package_win64/build/src\stackwalk.c:94
record_backtrace at /home/Administrator/buildbot/worker/package_win64/build/src\task.c:217 [inlined]
jl_throw at /home/Administrator/buildbot/worker/package_win64/build/src\task.c:417
jl_bounds_error_ints at /home/Administrator/buildbot/worker/package_win64/build/src\rtutils.c:183
getindex at .\array.jl:729 [inlined]
renumber_ssa at .\compiler/ssair\slot2ssa.jl:65 [inlined]
#241 at .\compiler/ssair\slot2ssa.jl:74 [inlined]
ssamap at .\compiler/ssair\ir.jl:429
renumber_ssa! at .\compiler/ssair\slot2ssa.jl:74 [inlined]
renumber_ssa! at .\compiler/ssair\slot2ssa.jl:73
jl_apply_generic at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:2219
construct_ssa! at .\compiler/ssair\slot2ssa.jl:859
just_construct_ssa at .\compiler/ssair\driver.jl:109
run_passes at .\compiler/ssair\driver.jl:114

on master of MRH.

See also #61 and #62

[oxinabox]

Thanks.
This tends to be that I broke one of the unwritten rules of when you are allowed to run Expr(:isdefined, :foo)
and hit the fallback SSAValue from JuliaLang/julia#31786.

Something will need to be added to:

MagneticReadHead.jl/src/pass.jl

Line 64 in 077943b

function created_on(ir)

to handle whatever the cause of this is.

[oxinabox]

I am really struggling to make a MVE of this.
I can reproduct this with Plots,
but so far not with anything simpler.

[oxinabox]

I am pretty sure
#61 and #62 are also the same issue.

I need to sit down with someone who understands the optimizer (pokes @Keno)
and dig into which of its assumptions I am violating.

[oxinabox]

I am going to close #61 and #62 just to keep the converstation in one place

[oxinabox]

Best MWE:

using MagneticReadHead, TimerOutputs
t = TimerOutput()
@run print_timer(t)

[oxinabox]

We are hitting this case
https://github.com/JuliaLang/julia/blob/faefe2ae64fb9a12824832582e2ddd3bc554d372/base/compiler/ssair/slot2ssa.jl#L656

[oxinabox]

MWE:

using MagneticReadHead

function danger19()
    y=2
    function inner()
        h=y
        y=12
        return h
    end
    inner()
end 

@run danger19()

[oxinabox]

#57
solves the danger19
MWE,
but not the others.

[KristofferC]

Don't think this should have been closed.