Failing to build on Mac OS X Catalina

[Voles]

I'm struggling to build the extension on Mac OS X. Using the following steps from the docs:

git clone git@github.com:citusdata/postgresql-hll.git
cd postgresql-hll
make CC=gcc CXX=gcc

I keep getting the following error / output:

gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Werror=vla -Wendif-labels -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing -fwrapv -Wno-unused-command-line-argument -mmacosx-version-min=10.12 -bundle -multiply_defined suppress -o hll.so src/hll.o src/MurmurHash3.o -L/Applications/Postgres.app/Contents/Versions/12/lib -L/Applications/Postgres.app/Contents/Versions/12/lib -L/Applications/Postgres.app/Contents/Versions/12/lib -Wl,-dead_strip_dylibs -bundle_loader /Applications/Postgres.app/Contents/Versions/12/bin/postgres -lstdc++
Undefined symbols for architecture x86_64:
"_AllocSetContextCreate", referenced from:
_setup_multiset in hll.o
"_heap_open", referenced from:
_get_extension_schema in hll.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [hll.so] Error 1

Environment

• Postgressapp Version 2.3.5 (80)
• PostgreSQL v12
• Mac OS Catalina (v10.15.6)

Is this a known issue? Let me know if I can provide any more information.

Thanks in advance!