Respond to commit review

+ Move NEWS.Rd entries to the bottom of the relevant section
+ Restore GET_STACKTRACE macro
+ Move open brace to conform to code style
+ Add copywrite comment block to Rcpp/exceptions_impl.h
+ Restore useless stack_trace API in Rcpp/routines.h
+ Restore RCPP_REGISTER(stack_trace)

Author: jpritikin

inst/NEWS.Rd

@@ -7,7 +7,6 @@
   \itemize{
     \item Changes in Rcpp API:
     \itemize{
-      \item \code{Rcpp::exception} is now thread-safe
       \item Safer \code{Rcpp_list*}, \code{Rcpp_lang*} and
       \code{Function.operator()} (Romain in \ghpr{1014}, \ghit{1015}).
       \item A number of \code{#nocov} markers were added (Dirk in
@@ -16,6 +15,9 @@
       Dirk in \ghpr{1038}).
       \item Scalar operations with a rhs matrix no longer change the
       matrix value (Qiang in \ghpr{1040} fixing (again) \ghit{365}).
+      \item \code{Rcpp::exception} and \code{Rcpp::stop} are now
+      thread-safe. Be cautioned that most of Rcpp continues to be not
+      thread-safe.
     }
     \item Changes in Rcpp Attributes:
     \itemize{

inst/include/Rcpp/exceptions.h

@@ -27,21 +27,21 @@
 #define RCPP_DEFAULT_INCLUDE_CALL true
 #endif
 
+#define GET_STACKTRACE() R_NilValue
+
 namespace Rcpp {
 
     // Throwing an exception must be thread-safe to avoid surprises w/ OpenMP.
     class exception : public std::exception {
     public:
         explicit exception(const char* message_, bool include_call = RCPP_DEFAULT_INCLUDE_CALL) :	// #nocov start
             message(message_),
-            include_call_(include_call)
-        {
+            include_call_(include_call) {
             record_stack_trace();
         }
         exception(const char* message_, const char*, int, bool include_call = RCPP_DEFAULT_INCLUDE_CALL) :
             message(message_),
-            include_call_(include_call)
-        {
+            include_call_(include_call) {
             record_stack_trace();
         }
         bool include_call() const {

inst/include/Rcpp/exceptions_impl.h

@@ -1,3 +1,22 @@
+// exceptions_impl.h: Rcpp R/C++ interface class library -- exceptions
+//
+// Copyright (C) 2020  Dirk Eddelbuettel and Romain Francois
+//
+// This file is part of Rcpp.
+//
+// Rcpp is free software: you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// Rcpp is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Rcpp.  If not, see <http://www.gnu.org/licenses/>.
+
 namespace Rcpp {
 #if defined(__GNUC__) || defined(__clang__)
     #if defined(_WIN32) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__CYGWIN__) || defined(__sun) || defined(_AIX) || defined(__MUSL__) || defined(__HAIKU__) || defined(__ANDROID__)

inst/include/Rcpp/routines.h

@@ -45,6 +45,7 @@ SEXP          rcpp_set_stack_trace(SEXP);
 std::string   demangle(const std::string& name);
 const char*   short_file_name(const char* );
 int*          get_cache(int n);
+SEXP          stack_trace( const char *file = "", int line = -1);
 SEXP          get_string_elt(SEXP s, R_xlen_t i);
 const char*   char_get_string_elt(SEXP s, R_xlen_t i);
 void          set_string_elt(SEXP s, R_xlen_t i, SEXP v);
@@ -156,6 +157,12 @@ inline attribute_hidden const char* short_file_name(const char* file) {
     return fun(file);
 }
 
+inline attribute_hidden SEXP stack_trace( const char *file = "", int line = -1){
+    typedef SEXP (*Fun)(const char*, int);
+    static Fun fun = GET_CALLABLE("stack_trace");
+    return fun(file, line);
+}
+
 inline attribute_hidden SEXP get_string_elt(SEXP s, R_xlen_t i){
     typedef SEXP (*Fun)(SEXP, R_xlen_t);
     static Fun fun = GET_CALLABLE("get_string_elt");

src/api.cpp

@@ -251,6 +251,12 @@ SEXP rcpp_can_use_cxx11() {				// #nocov start
 }							// #nocov end
 
 
+// [[Rcpp::register]]
+SEXP stack_trace(const char* file, int line) {
+    return R_NilValue;
+}
+
+
 // // [ [ Rcpp::register ] ]
 // void print(SEXP s) {
 //     Rf_PrintValue(s);           // defined in Rinternals.h

src/rcpp_init.cpp

@@ -100,6 +100,7 @@ void registerFunctions(){
     RCPP_REGISTER(endSuspendRNGSynchronization);
     RCPP_REGISTER(get_Rcpp_namespace)
     RCPP_REGISTER(get_cache)
+    RCPP_REGISTER(stack_trace)
     RCPP_REGISTER(get_string_elt)
     RCPP_REGISTER(char_get_string_elt)
     RCPP_REGISTER(set_string_elt)