julia 1.6: LLVM without zlib support chokes on compressed debug sections

[benlorenz]

I get some weird "error" messages during error-handling because I have compressed debug sections for some system libraries. According to strace the error happens when julia/LLVM tries to load /usr/lib/debug//lib64/libc.so.6.debug (moving that file away fixes the errors).

I have not noticed any problems apart from these messages and they are printed only once, either together with the first error or sometimes also without an error appearing (maybe because the error was within some try/catch).

               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.6.7 (2022-07-19)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> nonexistingvar
ERROR: error: failed to decompress '.debug_aranges', zlib is not available
error: failed to decompress '.debug_info', zlib is not available
error: failed to decompress '.debug_abbrev', zlib is not available
error: failed to decompress '.debug_line', zlib is not available
error: failed to decompress '.debug_str', zlib is not available
error: failed to decompress '.debug_line_str', zlib is not available
error: failed to decompress '.debug_loclists', zlib is not available
error: failed to decompress '.debug_rnglists', zlib is not available
UndefVarError: nonexistingvar not defined

julia> versioninfo()
Julia Version 1.6.7
Commit 3b76b25b64 (2022-07-19 15:11 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-11.0.1 (ORCJIT, tigerlake)
Environment:
  JULIA_DEPOT_PATH = /tmp/freshjuliadepot

If I read the history correctly zlib support was added to the LLVM builds in #42524, which is not in 1.6, and JuliaPackaging/Yggdrasil#3678 but LLVM 11.0.1 (for julia 1.6) was not rebuilt since.

PS: This does not happen with 1.8.