Harmless (?!) code leads to illegal instruction

[SimonDanisch]

record_reference_images = true
recordpath = "blah"
if record_reference_images
   cd(homedir()) do
       isdir(dirname(recordpath)) || run(`git clone git@github.com:SimonDanisch/ReferenceImages.git`)
       isdir(recordpath) && rm(recordpath)
   end
end

Unreachable reached at 0x7f4bd800eda3

signal (4): Illegal instruction
in expression starting at no file:0
cd at ./file.jl:99
unknown function (ip: 0x7f4bd800edc5)
jl_fptr_trampoline at /buildworker/worker/package_linux64/build/src/gf.c:1829
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
do_call at /buildworker/worker/package_linux64/build/src/interpreter.c:324
eval_value at /buildworker/worker/package_linux64/build/src/interpreter.c:428
eval_stmt_value at /buildworker/worker/package_linux64/build/src/interpreter.c:363 [inlined]
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:686
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:799
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7f4be357ff2f)
unknown function (ip: 0x9)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:808
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:787
jl_toplevel_eval_in at /buildworker/worker/package_linux64/build/src/builtins.c:622
eval at ./boot.jl:319
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
eval_user_input at /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.0/REPL/src/REPL.jl:85
macro expansion at /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.0/REPL/src/REPL.jl:117 [inlined]
#28 at ./task.jl:259
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
jl_apply at /buildworker/worker/package_linux64/build/src/julia.h:1536 [inlined]
start_task at /buildworker/worker/package_linux64/build/src/task.c:268
unknown function (ip: 0xffffffffffffffff)
Allocations: 263206 (Pool: 263125; Big: 81); GC: 0
Illegal instruction (core dumped)

Versioninfo:

julia> versioninfo()
Julia Version 1.0.0
Commit 5d4eaca0c9 (2018-08-08 20:58 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.0 (ORCJIT, skylake)

[JeffBezanson]

Worked for me. Maybe a stupid question, but should the blah directory exist?

[SimonDanisch]

No, I don't think so - at least it wasn't in the origin example, and it didn't need to in the MWE.
Actually, I just came home to my windows machine, where the behaviour is a bit different:

(the error comes when pressing enter)

if record_reference_images
          cd(homedir()) do
                 isdir(dirname(recordpath)) || run(`git clone git@github.com:SimonDanisch/ReferenceImages.git`)
                        isdir(recordpath) && rm(recordpath)
                           end
                           end
Cloning into 'ReferenceImages'...
Enter passphrase for key '/c/Users/sdani/.ssh/id_rsa':
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Unreachable reached at 00000000290D0F94

Please submit a bug report with steps to reproduce this fault, and any error messages that follow (in their entirety). Thanks.
Exception: EXCEPTION_ILLEGAL_INSTRUCTION at 0x290d0f94 -- cd at .\file.jl:85
in expression starting at no file:0
cd at .\file.jl:87
unknown function (ip: 00000000290D0FBB)
jl_fptr_trampoline at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:1829
jl_apply_generic at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:2182
do_call at /home/Administrator/buildbot/worker/package_win64/build/src\interpreter.c:324
eval_value at /home/Administrator/buildbot/worker/package_win64/build/src\interpreter.c:428
eval_stmt_value at /home/Administrator/buildbot/worker/package_win64/build/src\interpreter.c:363 [inlined]
eval_body at /home/Administrator/buildbot/worker/package_win64/build/src\interpreter.c:682
jl_interpret_toplevel_thunk_callback at /home/Administrator/buildbot/worker/package_win64/build/src\interpreter.c:799
unknown function (ip: FFFFFFFFFFFFFFFE)
unknown function (ip: 00000000106AEDAF)
unknown function (ip: 0000000000000009)
jl_toplevel_eval_flex at /home/Administrator/buildbot/worker/package_win64/build/src\toplevel.c:787
jl_toplevel_eval_in at /home/Administrator/buildbot/worker/package_win64/build/src\builtins.c:622
eval at .\boot.jl:319
jl_apply_generic at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:2182
eval_user_input at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.0\REPL\src\REPL.jl:85
macro expansion at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.0\REPL\src\REPL.jl:117 [inlined]
#28 at .\task.jl:259
jl_fptr_trampoline at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:1829
jl_apply_generic at /home/Administrator/buildbot/worker/package_win64/build/src\gf.c:2182
jl_apply at /home/Administrator/buildbot/worker/package_win64/build/src\julia.h:1536 [inlined]
start_task at /home/Administrator/buildbot/worker/package_win64/build/src\task.c:268
Allocations: 2684473 (Pool: 2683974; Big: 499); GC: 5

And then just the command alone:

julia> run(`git clone git@github.com:SimonDanisch/ReferenceImages.git`)
Cloning into 'ReferenceImages'...
Enter passphrase for key '/c/Users/sdani/.ssh/id_rsa':
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
ERROR: failed process: Process(`git clone git@github.com:SimonDanisch/ReferenceImages.git`, ProcessExited(128)) [128]
Stacktrace:
 [1] error(::String, ::Base.Process, ::String, ::Int64, ::String) at .\error.jl:42
 [2] pipeline_error at .\process.jl:695 [inlined]
 [3] #run#505(::Bool, ::Function, ::Cmd) at .\process.jl:653
 [4] run(::Cmd) at .\process.jl:651
 [5] top-level scope at none:0

[SimonDanisch]

I just run into the same error in some other unrelated, but also harmless looking code:
The error points to:
https://github.com/JuliaLang/julia/blob/v1.0.0/base/boot.jl#L581

Unreachable reached at 0x7fe1fe6630fb

signal (4): Illegal instruction
in expression starting at cell:1
check_top_bit at ./boot.jl:581 [inlined]
toUInt64 at ./boot.jl:692 [inlined]
Type at ./boot.jl:722 [inlined]
convert at ./number.jl:7 [inlined]
cconvert at ./essentials.jl:344 [inlined]
== at ./strings/string.jl:102 [inlined]
#84 at /root/.julia/packages/WebIO/myl19/src/providers/generic_http.jl:116

The code in generic_http is:
https://github.com/JuliaGizmos/WebIO.jl/blob/master/src/providers/generic_http.jl#L116

Seems like #25430 is unrelated?!

[JeffBezanson]

Would be good to test with #29406 and #29380 if you can.

[SimonDanisch]

Tested with latest master, which fixes #29468 but still fails with the issue here:

julia> cd(homedir()) do
                    run(`blah`)
                    rand(Bool) && nothing
                end
Unreachable reached at 0x7f5ee4334d73

signal (4): Illegal instruction
in expression starting at no file:0
cd at ./file.jl:99
unknown function (ip: 0x7f5ee4334d95)
jl_fptr_trampoline at /home/sd/juliastuff/julia/src/gf.c:1843
jl_apply_generic at /home/sd/juliastuff/julia/src/gf.c:2198
do_call at /home/sd/juliastuff/julia/src/interpreter.c:323
eval_value at /home/sd/juliastuff/julia/src/interpreter.c:411
eval_stmt_value at /home/sd/juliastuff/julia/src/interpreter.c:362 [inlined]
eval_body at /home/sd/juliastuff/julia/src/interpreter.c:768
jl_interpret_toplevel_thunk_callback at /home/sd/juliastuff/julia/src/interpreter.c:880
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7f5ef1d5b57f)
unknown function (ip: 0x7)
jl_interpret_toplevel_thunk at /home/sd/juliastuff/julia/src/interpreter.c:889
jl_toplevel_eval_flex at /home/sd/juliastuff/julia/src/toplevel.c:818
jl_toplevel_eval_in at /home/sd/juliastuff/julia/src/builtins.c:622
eval at ./boot.jl:319
jl_apply_generic at /home/sd/juliastuff/julia/src/gf.c:2198
eval_user_input at /home/sd/juliastuff/julia/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:85
macro expansion at /home/sd/juliastuff/julia/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:117 [inlined]
#26 at ./task.jl:259
jl_apply_generic at /home/sd/juliastuff/julia/src/gf.c:2198
jl_apply at /home/sd/juliastuff/julia/src/julia.h:1562 [inlined]
start_task at /home/sd/juliastuff/julia/src/task.c:504
unknown function (ip: 0xffffffffffffffff)
Allocations: 1138948 (Pool: 1138767; Big: 181); GC: 1
Illegal instruction (core dumped)

As you can see I reduced the example a bit... Right hand of short circuit doesn't matter - just seems to be important that the compiler can't infer whether it's true or false!
Doesn't crash without cd - since cd uses libuv and run as well, maybe there is something funky going on with libuv

[vtjnash]

Yeah, there's many cases where we can't handle errors with catch right now without segfaulting. Keno started work on a PR to fix that (#29158)

[SimonDanisch]

Oh wow^^ Well, seems like #29158 fixes this :)

[PetrKryslUCSD]

Is this crash related (segmentation violation)?

signal (11): Segmentation fault
in expression starting at /mnt/c/Users/PetrKrysl/Documents/Work-in-progress/H2Libjl/src/SolidMatrices.jl:16
jl_array_ptr_ref at /buildworker/worker/package_linux64/build/src/julia.h:785 [inlined]
body_attributes at /buildworker/worker/package_linux64/build/src/toplevel.c:404 [inlined]
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:761
resolve_globals at /buildworker/worker/package_linux64/build/src/method.c:34
jl_method_set_source at /buildworker/worker/package_linux64/build/src/method.c:559 [inlined]
jl_new_method at /buildworker/worker/package_linux64/build/src/method.c:628 [inlined]
jl_method_def at /buildworker/worker/package_linux64/build/src/method.c:790
eval_methoddef at /buildworker/worker/package_linux64/build/src/interpreter.c:310
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:659
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:799
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7f7b9db9294f)
unknown function (ip: 0x13)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:808
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:787
jl_eval_module_expr at /buildworker/worker/package_linux64/build/src/toplevel.c:233
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:616
jl_parse_eval_all at /buildworker/worker/package_linux64/build/src/ast.c:838
jl_load at /buildworker/worker/package_linux64/build/src/toplevel.c:821
include at ./boot.jl:317 [inlined]
include_relative at ./loading.jl:1038
include at ./sysimg.jl:29 [inlined]
include at /mnt/c/Users/PetrKrysl/Documents/Work-in-progress/H2Libjl/src/H2Libjl.jl:1
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
do_call at /buildworker/worker/package_linux64/build/src/interpreter.c:324
eval_value at /buildworker/worker/package_linux64/build/src/interpreter.c:428
eval_stmt_value at /buildworker/worker/package_linux64/build/src/interpreter.c:363 [inlined]
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:686
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:799
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7f7b9d00ea3f)
unknown function (ip: 0xffffffffffffffff)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:808
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:787
jl_eval_module_expr at /buildworker/worker/package_linux64/build/src/toplevel.c:233
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:616
jl_parse_eval_all at /buildworker/worker/package_linux64/build/src/ast.c:838
jl_load at /buildworker/worker/package_linux64/build/src/toplevel.c:821
include at ./boot.jl:317 [inlined]
include_relative at ./loading.jl:1038
_require at ./loading.jl:950
require at ./loading.jl:852
macro expansion at ./logging.jl:311 [inlined]
require at ./loading.jl:834
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
jl_apply at /buildworker/worker/package_linux64/build/src/julia.h:1536 [inlined]
call_require at /buildworker/worker/package_linux64/build/src/toplevel.c:441 [inlined]
eval_import_path at /buildworker/worker/package_linux64/build/src/toplevel.c:476
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:633
jl_eval_module_expr at /buildworker/worker/package_linux64/build/src/toplevel.c:233
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:616
jl_parse_eval_all at /buildworker/worker/package_linux64/build/src/ast.c:838
jl_load at /buildworker/worker/package_linux64/build/src/toplevel.c:821
include at ./boot.jl:317 [inlined]
include_relative at ./loading.jl:1038
include at ./sysimg.jl:29
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
include at ./client.jl:388
jl_fptr_trampoline at /buildworker/worker/package_linux64/build/src/gf.c:1829
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
do_call at /buildworker/worker/package_linux64/build/src/interpreter.c:324
eval_value at /buildworker/worker/package_linux64/build/src/interpreter.c:428
eval_stmt_value at /buildworker/worker/package_linux64/build/src/interpreter.c:363 [inlined]
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:686
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:799
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7f7b9b6fe94f)
unknown function (ip: 0xffffffffffffffff)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:808
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:787
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:734
jl_toplevel_eval_in at /buildworker/worker/package_linux64/build/src/builtins.c:622
eval at ./boot.jl:319
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
eval_user_input at /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.0/REPL/src/REPL.jl:85
macro expansion at /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.0/REPL/src/REPL.jl:117 [inlined]
#28 at ./task.jl:259
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2182
jl_apply at /buildworker/worker/package_linux64/build/src/julia.h:1536 [inlined]
start_task at /buildworker/worker/package_linux64/build/src/task.c:268
unknown function (ip: 0xffffffffffffffff)
Allocations: 7076016 (Pool: 7074879; Big: 1137); GC: 15
Segmentation fault (core dumped)

[JeffBezanson]

It's hard to say. If you haven't filed it yet, please file an issue with instructions for reproducing it. If it turns out to be a duplicate of something else we'll figure that out eventually.

[SimonDanisch]

I think it's related... I can reproduce it on julia 1.0, while i get an error on @Keno branch:

julia> c = h5open("mydata.h5", "r") do file
           read(file, "A")
       end
HDF5-DIAG: Error detected in HDF5 (1.10.0-patch1) thread 139890977341632:
  #000: ../../../src/H5O.c line 257 in H5Oopen(): unable to open object
    major: Object header
    minor: Can't open object
  #001: ../../../src/H5O.c line 1499 in H5O_open_name(): object not found
    major: Object header
    minor: Object not found
  #002: ../../../src/H5Gloc.c line 430 in H5G_loc_find(): can't find object
    major: Symbol table
    minor: Object not found
  #003: ../../../src/H5Gtraverse.c line 869 in H5G_traverse(): internal path traversal failed
    major: Symbol table
    minor: Object not found
  #004: ../../../src/H5Gtraverse.c line 641 in H5G_traverse_real(): traversal operator failed
    major: Symbol table
    minor: Callback failed
  #005: ../../../src/H5Gloc.c line 385 in H5G_loc_find_cb(): object 'A' doesn't exist
    major: Symbol table
    minor: Object not found