Another stab at #113

Author: kevinushey

src/barrier.cpp

@@ -135,7 +135,8 @@ SEXP set_current_error(SEXP cache, SEXP e){
 SEXP init_Rcpp_cache(){   
     SEXP getNamespaceSym = Rf_install("getNamespace"); // cannot be gc()'ed  once in symbol table
     Rcpp::Shield<SEXP> RcppString( Rf_mkString("Rcpp") );
-    Rcpp::Shield<SEXP> RCPP( Rf_eval(Rf_lang2( getNamespaceSym, RcppString ), R_GlobalEnv) ) ;
+    Rcpp::Shield<SEXP> call( Rf_lang2( getNamespaceSym, RcppString ) );
+    Rcpp::Shield<SEXP> RCPP( Rf_eval(call, R_GlobalEnv) ) ;
     Rcpp::Shield<SEXP> cache( Rf_allocVector( VECSXP, RCPP_CACHE_SIZE ) );
 
     // the Rcpp namespace