{"ast_node_type":"other","tokens":[{"end":68,"kind":"keyword","start":0,"text":"option_env!(\"CFG_VIRTUAL_RUST_SOURCE_BASE_DIR\"),"}]}
                    option_env!("CFG_VIRTUAL_RUST_SOURCE_BASE_DIR"),
                try_to_translate_real_to_virtual(
                    &sess.opts.real_rust_source_base_dir,