depends m4 &&

if spell_ok gcc; then
  persistent_read gcc GCC_COMPILER GCC_COMPILER || true
fi &&

# only allow dependency on g++ if g++ is installed, otherwise a cycle is created
if list_find "$GCC_COMPILER" "c++"; then
  optional_depends -sub CXX gcc \
                            "--enable-cxx" \
                            "--disable-cxx" \
                            "Enable C++ support?"
else
  OPTS="--disable-cxx $OPTS"
fi