Julia: Infinite goto loop returns an integer

[pwstokes225]

In the REPL, the following returns 1 instead of looping forever:

julia> (@label a; @goto a)
1

Observed on Julia 1.2:

julia> versioninfo()
Julia Version 1.2.0-rc3.0
Commit f18655ed3c (2019-08-12 20:32 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.1 (ORCJIT, sandybridge)
Environment:
  JULIA_NUM_THREADS = 4

[Keno]

Infinite loops without side effects are considered undefined behavior in LLVM and we inherit that assumption.

[Keno]

(Though this might be an issue with the interpreter instead, since that may not have been compiled).

[yuyichao]

(It seems to have been lowered to 1)

[JeffBezanson]

:sweat_smile:

[JeffBezanson]

I assume the bug is that it should return 42 instead? :stuck_out_tongue: