Remove comments from C and C++ files (Requires GCC)

remove_cxx_comments.sh

#/usr/bin/env bash
set -eu

USAGE="\nUSAGE: $0 -i INPUT_C_CXX_FILE -o OUTPUT_C_CXX_FILE [ -c G++_COMPILER  ]\n"

INPUT_FILE=''
OUTPUT_FILE=''
COMPILER='g++'

while [[ "$#" -gt 0 ]] ; do
    key="$1"
    case "${key}" in
        -i|--input)
            INPUT_FILE="$2"
            shift
            ;;
        -o|--output)
            OUTPUT_FILE="$2"
            shift
            ;;
        -c|--compiler)
            COMPILER="$2"
            shift
            ;;
        -h|--help)
            echo -e "${USAGE}"
            exit 0
            ;;
        *)
            >&2 echo -e "Unknown option [${key}]"
            >&2 echo -e "${USAGE}"
            exit 1
            ;;
    esac
    shift
done

HAS_ERRORS=''

if [[ -z "${INPUT_FILE}" ]] ; then
    HAS_ERRORS='true'
    >&2 echo -e 'Missing input file'
elif [[ ! -f "${INPUT_FILE}" ]] ; then
    HAS_ERRORS='true'
    >&2 echo -e "Input file not found or is not a regular file [${INPUT_FILE}]"
fi
if [[ -z "${OUTPUT_FILE}" ]] ; then
    HAS_ERRORS='true'
    >&2 echo -e 'Missing output file'
elif [[ "$(readlink -f "${INPUT_FILE}")" == "$(readlink -f "${OUTPUT_FILE}")" ]] ; then
    HAS_ERRORS='true'
    >&2 echo -e 'Output file must be different from input file'
fi
if [[ ! $(command -v "${COMPILER}") ]] ; then
    HAS_ERRORS='true'
    >&2 echo -e "Compiler not found [${COMPILER}]"
fi
if [[ -n "${HAS_ERRORS}" ]] ; then
    >&2 echo -e "${USAGE}"
    exit 2
fi

# Original ideas
# https://stackoverflow.com/a/2394040/865719
# https://stackoverflow.com/a/48434169/865719
"${COMPILER}" -fpreprocessed -dD -E -P "${INPUT_FILE}" -o "${OUTPUT_FILE}"

Test https://godbolt.org/z/xhYx3- (shows also the failure cases that I'm aware of)