just run into this when developing my package Traits.jl further, maybe someone recognizes this (it is quite difficult to get a minimal working example, but of course I will try as this blocks me currently) (running the key code block on its own) Unreachable reached at 0x13929e935 signal (4): Illegal instruction: 4 in expression starting at /Users/s.sahm/.julia/dev/Traits/test/syntax.jl:33 Type at ./none:0 normalize_func at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:203 #parse_traitsfunction#2 at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:106 parse_traitsfunction at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:16 [inlined] _traits_parsed at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:38 _traits at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:32 @traits at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:22 jl_invoke_julia_macro at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1040 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1102 jl_parse_eval_all at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:857 include_string at ./loading.jl:1075 include_string at /Users/s.sahm/.julia/packages/CodeTools/kosGY/src/eval.jl:30 unknown function (ip: 0x119575c92) #188 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:111 withpath at /Users/s.sahm/.julia/packages/CodeTools/kosGY/src/utils.jl:30 withpath at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:9 #187 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:110 [inlined] with_logstate at ./logging.jl:395 with_logger at ./logging.jl:491 [inlined] #186 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:109 [inlined] hideprompt at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/repl.jl:141 macro expansion at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:108 [inlined] macro expansion at /Users/s.sahm/.julia/packages/Media/ItEPc/src/dynamic.jl:24 [inlined] eval at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:104 unknown function (ip: 0x11956acba) jl_apply at /Users/julia/buildbot/worker/package_macos64/build/src/./julia.h:1631 [inlined] jl_f__apply at /Users/julia/buildbot/worker/package_macos64/build/src/builtins.c:627 macro expansion at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:36 [inlined] #172 at ./task.jl:333 unknown function (ip: 0x1195254fc) jl_apply at /Users/julia/buildbot/worker/package_macos64/build/src/./julia.h:1631 [inlined] start_task at /Users/julia/buildbot/worker/package_macos64/build/src/task.c:659 Allocations: 73733351 (Pool: 73717314; Big: 16037); GC: 80 or here another version (running the key code blog as part of @test/@testset) Unreachable reached at 0x13d1f9095 signal (4): Illegal instruction: 4 in expression starting at /Users/s.sahm/.julia/dev/Traits/test/syntax.jl:25 Type at ./none:0 normalize_func at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:203 #parse_traitsfunction#2 at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:106 parse_traitsfunction at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:16 [inlined] _traits_parsed at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:38 _traits at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:32 @traits_test at /Users/s.sahm/.julia/dev/Traits/src/ExtraHelpers.jl:17 jl_invoke_julia_macro at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1040 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1102 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1145 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1112 jl_parse_eval_all at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:857 include_string at ./loading.jl:1075 include_string at /Users/s.sahm/.julia/packages/CodeTools/kosGY/src/eval.jl:30 unknown function (ip: 0x13d197ab2) #188 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:111 withpath at /Users/s.sahm/.julia/packages/CodeTools/kosGY/src/utils.jl:30 withpath at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:9 #187 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:110 [inlined] with_logstate at ./logging.jl:395 with_logger at ./logging.jl:491 [inlined] #186 at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:109 [inlined] hideprompt at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/repl.jl:141 macro expansion at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:108 [inlined] macro expansion at /Users/s.sahm/.julia/packages/Media/ItEPc/src/dynamic.jl:24 [inlined] eval at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:104 unknown function (ip: 0x13d19259a) jl_apply at /Users/julia/buildbot/worker/package_macos64/build/src/./julia.h:1631 [inlined] jl_f__apply at /Users/julia/buildbot/worker/package_macos64/build/src/builtins.c:627 macro expansion at /Users/s.sahm/.julia/packages/Atom/cYxbS/src/eval.jl:36 [inlined] #172 at ./task.jl:333 unknown function (ip: 0x1167444fc) jl_apply at /Users/julia/buildbot/worker/package_macos64/build/src/./julia.h:1631 [inlined] start_task at /Users/julia/buildbot/worker/package_macos64/build/src/task.c:659 Allocations: 59821895 (Pool: 59808242; Big: 13653); GC: 65

If you have Julia master and have access to Linux, maybe you can try the new bug reporting API julia --bug-report=rr: https://github.com/JuliaLang/julia/pull/35494

running on mac, and julia 1.3.1, now giving it a try with most recent stable julia, and will think about trying it thereafter with julia master thanks for the pointer!

unfortunately also with julia 1.4.1 I get an Unreachable Reached Unreachable reached at 0x1192773d5 signal (4): Illegal instruction: 4 in expression starting at REPL[15]:1 Type##kw at ./util.jl:753 normalize_func at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:203 #parse_traitsfunction#2 at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:106 parse_traitsfunction at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Parsing.jl:16 [inlined] _traits_parsed at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:38 _traits at /Users/s.sahm/.julia/dev/Traits/src/Syntax/Syntax.jl:32 @traits_test at /Users/s.sahm/.julia/dev/Traits/src/ExtraHelpers.jl:17 jl_invoke_julia_macro at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1039 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1101 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1144 jl_expand_macros at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1111 jl_expand_with_loc at /Users/julia/buildbot/worker/package_macos64/build/src/ast.c:1179 jl_toplevel_eval_flex at /Users/julia/buildbot/worker/package_macos64/build/src/toplevel.c:634 jl_toplevel_eval_flex at /Users/julia/buildbot/worker/package_macos64/build/src/toplevel.c:764 jl_toplevel_eval at /Users/julia/buildbot/worker/package_macos64/build/src/toplevel.c:823 [inlined] jl_toplevel_eval_in at /Users/julia/buildbot/worker/package_macos64/build/src/toplevel.c:843 eval at ./boot.jl:331 eval_user_input at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.4/REPL/src/REPL.jl:86 macro expansion at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.4/REPL/src/REPL.jl:118 [inlined] #26 at ./task.jl:358 jl_apply at /Users/julia/buildbot/worker/package_macos64/build/src/./julia.h:1700 [inlined] start_task at /Users/julia/buildbot/worker/package_macos64/build/src/task.c:687 Allocations: 49211149 (Pool: 49204206; Big: 6943); GC: 54

People should get a special medal when they get that error, like a badge of honour or something. :medal_military: /end of non-constructive comment.

I created a bug report and actually was able to minify the case to pure Julia, https://github.com/JuliaLang/julia/issues/35698#issuecomment-622947669 here the key piece of code with which you can replicate the Unreachable reached error Base.@kwdef struct UnreachableReached{T} type::Type{T} end type1 = Tuple{Array{T1,1} where T1} UnreachableReached{type1}(type = type1) type2 = Tuple{Array{T2,1}} where T2 UnreachableReached{type2}(type = type2) There is actually a simple workaround in such situations: Using positional arguments instead of named arguments seems to work fine.

Unreachable reached at 0x13929e935

Internals & Design

StefanKarpinski May 1, 2020, 3:22pm 6

Any time you reach the unreachable, it is a time for celebration. And a bug report, pls.

Unreachable reached, v1.11.5: file github issue, or discuss here first?

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Unreachable reached at 0x13929e935

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