HACK: just define preserve_list in the global env

Author: bkietz

inst/include/cpp11/protect.hpp

@@ -14,6 +14,8 @@
 #include "R_ext/Utils.h"  // for R_CheckUserInterrupt
 #include "Rversion.h"     // for R_VERSION, R_Version
 
+#include <iostream>
+
 #if defined(R_VERSION) && R_VERSION >= R_Version(3, 5, 0)
 #define HAS_UNWIND_PROTECT
 #endif
@@ -288,8 +290,18 @@ static struct {
       // The .preserve_list singleton is a member of cpp11::: and is managed by the R
       // runtime. It cannot be constructed a header since many translation units may be
       // compiled, resulting in unrelated instances of each static variable.
-      SEXP ns = safe[Rf_findVarInFrame](R_NamespaceRegistry, safe[Rf_install]("cpp11"));
-      list_singleton = safe[Rf_findVar](safe[Rf_install](".preserve_list"), ns);
+
+      // FIXME how can we create the cpp11 namespace when it doesn't already exist?
+      SEXP list_singleton_sym = safe[Rf_install](".cpp11_preserve_list");
+
+      list_singleton = safe[Rf_findVarInFrame](R_GlobalEnv, list_singleton_sym);
+
+      if (list_singleton == R_UnboundValue) {
+        list_singleton = PROTECT(Rf_cons(R_NilValue, R_NilValue));
+        R_PreserveObject(list_singleton);
+        UNPROTECT(1);
+        safe[Rf_defineVar](list_singleton_sym, list_singleton, R_GlobalEnv);
+      }
     }
 
     return list_singleton;

inst/include/cpp11/r_vector.hpp

@@ -766,7 +766,9 @@ inline r_vector<T>::r_vector(const r_vector<T>& rhs)
 
 template <typename T>
 inline r_vector<T>::r_vector(r_vector<T>&& rhs)
-    : cpp11::r_vector<T>(rhs), protect_(preserved.insert(data_)), capacity_(rhs.capacity_) {
+    : cpp11::r_vector<T>(rhs),
+      protect_(preserved.insert(data_)),
+      capacity_(rhs.capacity_) {
   rhs.data_ = R_NilValue;
   rhs.protect_ = R_NilValue;
 }