Assembly to raw shellcode or runnable program

shcc.sh

#!/usr/bin/zsh

ARCH="elf64"
TARGET=""
MODE="raw"

while getopts "a:f:e" arg; do
        case $arg in

        a)
                echo "Setting arch to -> $OPTARG"
                ARCH=$OPTARG
                ;;
        f)
                TARGET=$OPTARG
                ;;
        e)
                MODE="exec"
                ;;

        esac
done

if [ -z "$TARGET" ];then
        echo "Error : No file specified"
        exit -1
fi

echo "Compiling $TARGET (arch $ARCH)"

nasm -f $ARCH $TARGET -o .tmp_sc

if [[ "$MODE" == "exec" ]];then
        ld .tmp_sc -o payload.elf
else
        objcopy -O binary -j .text .tmp_sc payload.bin
        echo "Extracted shellcode of length -> $(wc -c payload.bin)"
fi

rm .tmp_sc