Syntax error fixes parsing more elaborate parameter pack arguments

that are function pointers and member function pointers.

  template <typename... V> struct VariadicParms {
    void ParmsFuncPtrPtr(int (*)(V*...)) {}
    void ParmsFuncPtrPtrRef(int (*)(V*&...)) {}
    void ParmsFuncPtrPtrRValueRef(int (*)(V*&&...)) {}
    void ParmsFuncPtrRef(int (*)(V&...)) {}
    void ParmsFuncPtrRValueRef(int (*)(V&&...)) {}

    void ParmsMemFuncPtrPtr(int (KlassMemFuncs::*)(V*...)) {}
    void ParmsMemFuncPtrPtrRef(int (KlassMemFuncs::*)(V*&...)) {}
    void ParmsMemFuncPtrPtrRValueRef(int (KlassMemFuncs::*)(V*&&...)) {}
    void ParmsMemFuncPtrRef(int (KlassMemFuncs::*)(V&...)) {}
    void ParmsMemFuncPtrRValueRef(int (KlassMemFuncs::*)(V&&...)) {}
  };

  %template(VariadicParms0) VariadicParms<>;
  %template(VariadicParms1) VariadicParms<A>;

  Also in various other places such as within noexcept specifiers:

    template<typename T, typename... Args>
    void emplace(Args &&... args) noexcept(
        std::is_nothrow_constructible<T, Args &&...>::value);

Issue #1863

CHANGES.current

@@ -7,6 +7,33 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.2.0 (in progress)
 ===========================
 
+2022-12-29: wsfulton
+            #1863 Syntax error fixes parsing more elaborate parameter pack arguments that are
+            used in function pointers, member function pointers:
+
+              template <typename... V> struct VariadicParms {
+                void ParmsFuncPtrPtr(int (*)(V*...)) {}
+                void ParmsFuncPtrPtrRef(int (*)(V*&...)) {}
+                void ParmsFuncPtrPtrRValueRef(int (*)(V*&&...)) {}
+                void ParmsFuncPtrRef(int (*)(V&...)) {}
+                void ParmsFuncPtrRValueRef(int (*)(V&&...)) {}
+
+                void ParmsMemFuncPtrPtr(int (KlassMemFuncs::*)(V*...)) {}
+                void ParmsMemFuncPtrPtrRef(int (KlassMemFuncs::*)(V*&...)) {}
+                void ParmsMemFuncPtrPtrRValueRef(int (KlassMemFuncs::*)(V*&&...)) {}
+                void ParmsMemFuncPtrRef(int (KlassMemFuncs::*)(V&...)) {}
+                void ParmsMemFuncPtrRValueRef(int (KlassMemFuncs::*)(V&&...)) {}
+              };
+
+              %template(VariadicParms0) VariadicParms<>;
+              %template(VariadicParms1) VariadicParms<A>;
+
+            Also in various other places such as within noexcept specifiers:
+
+              template<typename T, typename... Args>
+              void emplace(Args &&... args) noexcept(
+                  std::is_nothrow_constructible<T, Args &&...>::value);
+
 2022-12-27: wsfulton
             Fix instantiation of variadic class templates containing parameter pack arguments that
             are function pointers.

Examples/test-suite/cpp11_variadic_templates.i

@@ -147,7 +147,6 @@ struct KlassMemFuncs {
   int memfunc3() { return 3; }
 };
 template <typename... V> struct VariadicParms {
-public:
   void ParmsVal(V... vparms_v) {}
   void ParmsPtr(V*... vparms_p) {}
   void ParmsPtrRef(V*&... vparms_pr) {}
@@ -157,9 +156,20 @@ public:
   void ParmsConstRef(const V&... vparms_cr) {}
 
   void ParmsFuncPtrVal(int (*)(V...)) {}
+  void ParmsFuncPtrPtr(int (*)(V*...)) {}
+  void ParmsFuncPtrPtrRef(int (*)(V*&...)) {}
+  void ParmsFuncPtrPtrRValueRef(int (*)(V*&&...)) {}
+  void ParmsFuncPtrRef(int (*)(V&...)) {}
+  void ParmsFuncPtrRValueRef(int (*)(V&&...)) {}
+  void ParmsFuncPtrConstRef(int (*)(const V&...)) {}
+
   void ParmsMemFuncPtrVal(int (KlassMemFuncs::*)(V...)) {}
-// TODO
+  void ParmsMemFuncPtrPtr(int (KlassMemFuncs::*)(V*...)) {}
-//  void ParmsFuncPtrRef(int (*)(V&...)) {}
+  void ParmsMemFuncPtrPtrRef(int (KlassMemFuncs::*)(V*&...)) {}
+  void ParmsMemFuncPtrPtrRValueRef(int (KlassMemFuncs::*)(V*&&...)) {}
+  void ParmsMemFuncPtrRef(int (KlassMemFuncs::*)(V&...)) {}
+  void ParmsMemFuncPtrRValueRef(int (KlassMemFuncs::*)(V&&...)) {}
+  void ParmsMemFuncPtrConstRef(int (KlassMemFuncs::*)(const V&...)) {}
 };
 %}
 
@@ -209,3 +219,17 @@ template void Container::notifyMyTypes<>(void (tt)());
 template void Container::notifyMyTypes<int>(void (tt)(int));
 template void Container::notifyMyTypes<int, double>(void (tt)(int, double));
 %}
+
+// #1863
+%inline %{
+#include <type_traits>
+class EmplaceContainer {
+public:
+template<typename T, typename... Args>
+void emplace(Args &&... args) noexcept(
+    std::is_nothrow_constructible<T, Args &&...>::value) {}
+};
+%}
+
+%template(emplace) EmplaceContainer::emplace<int,A>;
+//%template(emplace) EmplaceContainer::emplace<int,A,B,C>;

Source/CParse/parser.y

@@ -1684,7 +1684,7 @@ static String *add_qualifier_to_declarator(SwigType *type, SwigType *qualifier)
 %type <type>     templcpptype cpptype classkey classkeyopt;
 %type <id>       access_specifier;
 %type <node>     base_specifier;
-%type <str>      variadic;
+%type <str>      variadic_opt;
 %type <type>     type rawtype type_right anon_bitfield_type decltype ;
 %type <bases>    base_list inherit raw_inherit;
 %type <dtype>    definetype def_args etype default_delete deleted_definition explicit_default;
@@ -5877,11 +5877,12 @@ direct_declarator : idcolon {
 		  }
                   ;
 
-abstract_declarator : pointer {
+abstract_declarator : pointer variadic_opt {
 		    $$.type = $1;
                     $$.id = 0;
 		    $$.parms = 0;
 		    $$.have_parms = 0;
+		    if ($2) SwigType_add_variadic($$.type);
                   }
                   | pointer direct_abstract_declarator { 
                      $$ = $2;
@@ -5889,19 +5890,21 @@ abstract_declarator : pointer {
 		     $$.type = $1;
 		     Delete($2.type);
                   }
-                  | pointer AND {
+                  | pointer AND variadic_opt {
 		    $$.type = $1;
 		    SwigType_add_reference($$.type);
 		    $$.id = 0;
 		    $$.parms = 0;
 		    $$.have_parms = 0;
+		    if ($3) SwigType_add_variadic($$.type);
 		  }
-                  | pointer LAND {
+                  | pointer LAND variadic_opt {
 		    $$.type = $1;
 		    SwigType_add_rvalue_reference($$.type);
 		    $$.id = 0;
 		    $$.parms = 0;
 		    $$.have_parms = 0;
+		    if ($3) SwigType_add_variadic($$.type);
 		  }
                   | pointer AND direct_abstract_declarator {
 		    $$ = $3;
@@ -5942,19 +5945,21 @@ abstract_declarator : pointer {
 		      Delete($2.type);
 		    }
                   }
-                  | AND {
+                  | AND variadic_opt {
                     $$.id = 0;
                     $$.parms = 0;
 		    $$.have_parms = 0;
                     $$.type = NewStringEmpty();
 		    SwigType_add_reference($$.type);
+		    if ($2) SwigType_add_variadic($$.type);
                   }
-                  | LAND {
+                  | LAND variadic_opt {
                     $$.id = 0;
                     $$.parms = 0;
 		    $$.have_parms = 0;
                     $$.type = NewStringEmpty();
 		    SwigType_add_rvalue_reference($$.type);
+		    if ($2) SwigType_add_variadic($$.type);
                   }
                   | idcolon DSTAR { 
 		    $$.type = NewStringEmpty();
@@ -6155,7 +6160,9 @@ rawtype        : type_qualifier type_right {
                    $$ = $2;
 	           SwigType_push($$,$1);
                }
-               | type_right { $$ = $1; }
+	       | type_right {
+		  $$ = $1;
+	       }
                | type_right type_qualifier {
 		  $$ = $1;
 	          SwigType_push($$,$2);
@@ -6876,7 +6883,7 @@ exprcompound   : expr PLUS expr {
                }
                ;
 
-variadic      : ELLIPSIS {
+variadic_opt  : ELLIPSIS {
 	        $$ = NewString("...");
 	      }
 	      | empty {
@@ -6921,7 +6928,7 @@ base_list      : base_specifier {
 
 base_specifier : opt_virtual {
 		 $<intvalue>$ = cparse_line;
-	       } idcolon variadic {
+	       } idcolon variadic_opt {
 		 $$ = NewHash();
 		 Setfile($$,cparse_file);
 		 Setline($$,$<intvalue>2);
@@ -6940,7 +6947,7 @@ base_specifier : opt_virtual {
                }
 	       | opt_virtual access_specifier {
 		 $<intvalue>$ = cparse_line;
-	       } opt_virtual idcolon variadic {
+	       } opt_virtual idcolon variadic_opt {
 		 $$ = NewHash();
 		 Setfile($$,cparse_file);
 		 Setline($$,$<intvalue>3);