diff --git a/src/rinterface_extra.c b/src/rinterface_extra.c index 6bf1148422..222fbad26d 100644 --- a/src/rinterface_extra.c +++ b/src/rinterface_extra.c @@ -8657,6 +8657,7 @@ SEXP R_igraph_add_env(SEXP graph) { SET_CLASS(result, Rf_duplicate(GET_CLASS(graph))); } +#if defined(R_VERSION) && R_VERSION >= R_Version(4, 1, 0) // Get the base namespace SEXP base_ns = PROTECT(R_FindNamespace(Rf_mkString("base"))); px++; // Get the emptyenv function @@ -8665,6 +8666,9 @@ SEXP R_igraph_add_env(SEXP graph) { SEXP empty_env = PROTECT(Rf_eval(Rf_lang1(empty_env_fun), R_GlobalEnv)); px++; // Evaluate the call SEXP env = PROTECT(R_NewEnv(empty_env, 0, 0)); px++; +#else + SEXP env = Rf_allocSExp(ENVSXP); +#endif SET_VECTOR_ELT(result, igraph_t_idx_env, env);