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Author: krlmlr

inst/include/Rcpp/protection/Shield.h

@@ -26,6 +26,8 @@ namespace Rcpp{
     }
 
     inline void Rcpp_unprotect(int i){
+        // Prefer this function over UNPROTECT() in Rcpp so that all
+        // balance checks errors by rchk are contained at one location (#892)
         UNPROTECT(i);
     }
 

inst/include/Rcpp/vector/no_init.h

@@ -37,6 +37,8 @@ class no_init_vector {
 
     template <int RTYPE>
     operator Vector<RTYPE, PreserveStorage>() const {
+        // Explicitly protect temporary vector to avoid false positive
+        // with rchk (#892)
         SEXP x = PROTECT(Rf_allocVector(RTYPE, size));
         Vector<RTYPE, PreserveStorage> ret(x);
         UNPROTECT(1);