enable `-gz`

[vtjnash]

It seems like this may shrink some things quite significantly, per https://github.com/JuliaLang/julia/pull/45631 (also could enable zstd instead of zlib, which likely has better performance and compression ratios, but that option is more recent)

[imciner2]

Does that only compress the debug sections? I think a lot of the binaries here are built without debug information (e.g. the default recommended CMake configuration is Release, same with Meson and Rust), so it might not actually make a large difference to the Ygg binaries.

[benlorenz]

I think it would be good to get a zlib enabled LLVM into julia-1.6 before creating compressed debug sections in jlls (at least if they target 1.6 as well).

This is not really nice user experience, see https://github.com/JuliaLang/julia/issues/47727:

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

julia> someerror
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: someerror not defined

(I have compressed debug sections in some system libraries)

[ViralBShah]

I believe we do this.