Darwin 8.6.2 installation problem

Created by: jtdaugherty

I attempted to use ghcup to install GHC 8.6.2 on OS X (High Sierra, 10.13.6). After ghcup fetched the GHC package and began installation, I ultimately saw a great many lines like

/Library/Developer/CommandLineTools/usr/bin/ranlib: file: /Users/.../.ghcup/ghc/8.6.2/lib/ghc-8.6.2/rts/libHSrts_thr_p.a(elf_reloc_aarch64.thr_p_o) has no symbols
/Library/Developer/CommandLineTools/usr/bin/ranlib: file: /Users/.../.ghcup/ghc/8.6.2/lib/ghc-8.6.2/rts/libHSrts_thr_p.a(elf_util.thr_p_o) has no symbols
/Library/Developer/CommandLineTools/usr/bin/ranlib: file: /Users/.../.ghcup/ghc/8.6.2/lib/ghc-8.6.2/rts/libHSrts_thr_p.a(Select.thr_p_o) has no symbols

and then the installation terminated with

"utils/ghc-cabal/dist-install/build/tmp/ghc-cabal-bindist" copy libraries/ghc-prim dist-install "strip" '' '/Users/.../.ghcup/ghc/8.6.2' '/Users/.../.ghcup/ghc/8.6.2/lib/ghc-8.6.2' '/Users/.../.ghcup/ghc/8.6.2/share/doc/ghc-8.6.2/html/libraries' 'v p dyn'
dyld: Library not loaded: /usr/local/opt/gmp/lib/libgmp.10.dylib
  Referenced from: /private/var/folders/lm/ybj5rc1d5mq7523vdb2fry240000gn/T/tmp.M17dAytH/ghc-8.6.2/libraries/base/dist-install/build/libHSbase-4.12.0.0-ghc8.6.2.dylib
  Reason: image not found
make[1]: *** [install_packages] Abort trap: 6
make: *** [install] Error 2
Failed to install, consider updating this script via: ghcup upgrade