'cabal build all' failing on Mac

i’m trying to install and run cardano-node on macOS Big Sur. Everything is working up until cabal tries to build the unix-bytestring package on ‘cabal build all’ command:

Failed to build unix-bytestring-
Build log (
/Users/username/.cabal/logs/ghc-8.10.4/nx-bytstrng- ):
Warning: unix-bytestring.cabal:58:40: version operators used. To use version
operators the package needs to specify at least 'cabal-version: >= 1.8'.
Configuring unix-bytestring-
Preprocessing library for unix-bytestring-
Iovec.hsc:67:9: warning: 'hsc_alignment' macro redefined [-Wmacro-redefined]
#define hsc_alignment(t ) hsc_printf (     "%lu", (unsigned long) offsetof(struct {char x__; t (y__); }, y__));

not sure if this is an issue with the c compiler or what.

any help is appreciated. thank you!