Make.conf : What does this code do?

[Mayhem30]

I've had a file in my home directory (ports-config.sh) for over a year now and have no idea why I saved it.

#!/usr/local/bin/bash

if [ `whoami` != 'root' ] ; then
   echo "You must be root to do this."
   exit
fi

export SCRIPTSDIR="/usr/ports/Mk/Scripts"
export PORTSDIR="/usr/ports"
export MAKE="/usr/bin/make"

echo "# After making any changes to this file, you must run
# synth prepare-system

# /usr/ports/Mk/bsd.options.desc.mk
OPTIONS_UNSET = X11 CUPS

DEFAULT_VERSIONS += ssl=openssl php=7.1 mysql=5.6
" > /usr/local/etc/synth/LiveSystem-make.conf

/bin/sh ${PORTSDIR}/Mk/Scripts/ports_env.sh |
grep '^export [^;&]*' |
sed -e 's,^export ,,' -e 's,=",=,' -e 's,"$,,' >> /usr/local/etc/synth/LiveSystem-make.conf

This creates a /usr/local/etc/synth/LiveSystem-make.conf and includes :

# After making any changes to this file, you must run
# synth prepare-system

# /usr/ports/Mk/bsd.options.desc.mk
OPTIONS_UNSET = X11 CUPS

DEFAULT_VERSIONS += ssl=openssl php=7.1 mysql=5.6

_CCVERSION_921dbbb2=FreeBSD clang version 10.0.1 (git@github.com:llvm/llvm-project.git llvmorg-10.0.1-0-gef32c611aa2) Target: x86_64-unknown-freebsd12.3 Thread model: posix InstalledDir: /usr/bin
_ALTCCVERSION_921dbbb2=none
_CXXINTERNAL_acaad9ca=FreeBSD clang version 10.0.1 (git@github.com:llvm/llvm-project.git llvmorg-10.0.1-0-gef32c611aa2) Target: x86_64-unknown-freebsd12.3 Thread model: posix InstalledDir: /usr/bin "/usr/bin/ld" "--eh-frame-hdr" "-dynamic-linker" "/libexec/ld-elf.so.1" "--hash-style=both" "--enable-new-dtags" "-o" "a.out" "/usr/lib/crt1.o" "/usr/lib/crti.o" "/usr/lib/crtbegin.o" "-L/usr/lib" "/dev/null" "-lc++" "-lm" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "/usr/lib/crtend.o" "/usr/lib/crtn.o"
CC_OUTPUT_921dbbb2_58173849=yes
CC_OUTPUT_921dbbb2_9bdba57c=yes
CC_OUTPUT_921dbbb2_6a4fe7f5=yes
CC_OUTPUT_921dbbb2_6bcac02b=yes
CC_OUTPUT_921dbbb2_67d20829=yes
CC_OUTPUT_921dbbb2_bfa62e83=yes
CC_OUTPUT_921dbbb2_f0b4d593=yes
CC_OUTPUT_921dbbb2_308abb44=yes
CC_OUTPUT_921dbbb2_f00456e5=yes
CC_OUTPUT_921dbbb2_65ad290d=yes
CC_OUTPUT_921dbbb2_f2776b26=yes
CC_OUTPUT_921dbbb2_b2657cc3=yes
CC_OUTPUT_921dbbb2_380987f7=yes
CC_OUTPUT_921dbbb2_160933ec=yes
CC_OUTPUT_921dbbb2_fb62803b=yes
_OBJC_CCVERSION_921dbbb2=FreeBSD clang version 10.0.1 (git@github.com:llvm/llvm-project.git llvmorg-10.0.1-0-gef32c611aa2) Target: x86_64-unknown-freebsd12.3 Thread model: posix InstalledDir: /usr/bin
_OBJC_ALTCCVERSION_921dbbb2=none
ARCH=amd64
OPSYS=FreeBSD
_OSRELEASE=12.3-RELEASE-p3
OSREL=12.3
OSVERSION=1203000
_PERL5_FROM_BIN=5.32.1
PYTHONBASE=/usr/local
HAVE_COMPAT_IA32_KERN=YES
_SMP_CPUS=16
CONFIGURE_MAX_CMD_LEN=524288
HAVE_PORTS_ENV=1

What do all these _CC*, _ALT*, "CC_OUTPUT_*" lines even do?