ensure noreturn attribute is set on Rf_error in C++

git-svn-id: https://svn.r-project.org/R/trunk@87911 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: ripley

doc/NEWS.Rd

@@ -389,6 +389,10 @@
       \item There are a new functions \code{asRboolean} and
       \code{asBool}, variants of \code{asLogical} more suited to
       converting logical arguments to \code{Rboolean} or to \code{bool}. 
+
+      \item Header \file{R_exts/Error.h} now ensures that
+      \code{Rf_error} and similar are maeked with the \code{noreturn}
+      attribute from C++ under all compilers.
     }
   }
 

src/include/R_ext/Error.h

@@ -26,7 +26,7 @@
 #ifndef R_ERROR_H_
 #define R_ERROR_H_
 
-#include <R_ext/Print.h>
+#include <R_ext/Print.h> // for R_PRINTF_FORMAT
 
 #ifdef  __cplusplus
 extern "C" {
@@ -40,7 +40,7 @@ extern "C" {
  */
 #if defined NORET
 #elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202301L)
-// gcc 15 and clang 19/20
+// gcc 15 and clang 19-
 # define NORET [[noreturn]]
 #elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201102L
 # define NORET _Noreturn
@@ -52,10 +52,19 @@ extern "C" {
 # define NORET
 #endif
 
+#ifdef  __cplusplus
+// Only supported in C++ >= 11, but that is all current R supports
+// Defining NORET caused conflict in many C++-using packages
+[[noreturn]] void Rf_error(const char *, ...) R_PRINTF_FORMAT(1, 2);
+
+[[noreturn]] void UNIMPLEMENTED(const char *);
+[[noreturn]] void WrongArgCount(const char *);
+#else
 NORET void Rf_error(const char *, ...) R_PRINTF_FORMAT(1, 2);
 
 NORET void UNIMPLEMENTED(const char *);
 NORET void WrongArgCount(const char *);
+#endif
 
 void Rf_warning(const char *, ...) R_PRINTF_FORMAT(1,2);