Fix syntax error parsing variadic template parameter pack arguments

that are function pointers

Issue #1863

CHANGES.current

@@ -7,6 +7,10 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.2.0 (in progress)
 ===========================
 
+2022-12-23: wsfulton
+            #1863 Fix syntax error parsing variadic template parameter pack arguments that
+            are function pointers.
+
 2022-12-22: wsfulton
             Complete support for C++11 variadic templates. Support was previously limited
             to just one template parameter. Now zero or more template parameters are supported.

Examples/test-suite/cpp11_variadic_templates.i

@@ -143,15 +143,38 @@ public:
 %inline %{
 template <typename... V> struct VariadicParms {
 public:
+  void ParmsVal(V... vparms_v) {}
   void ParmsPtr(V*... vparms_p) {}
   void ParmsPtrRef(V*&... vparms_pr) {}
   void ParmsPtrRValueRef(V*&&... vparms_rvr) {}
-  void ParmsVal(V... vparms_v) {}
   void ParmsRef(V&... vparms_r) {}
+  void ParmsRValueRef(V&&... vparms_r) {}
   void ParmsConstRef(const V&... vparms_cr) {}
+
+// TODO
+//  void ParmsFuncPtr(int (*)(V...)) {}
 };
 %}
 
 %template(VariadicParms1) VariadicParms<A>;
 %template(VariadicParms2) VariadicParms<A,B>;
 %template(VariadicParms3) VariadicParms<A,B,C>;
+
+
+// #1863
+%inline %{
+class Container {
+public:
+template<typename... Args>
+static void notifyMyTypes(void (fn)(Args...));
+};
+%}
+%{
+template<typename... Args>
+  void Container::notifyMyTypes(void (fn)(Args...)) {}
+
+// Explicit template instantiations
+template void Container::notifyMyTypes<>(void (tt)());
+template void Container::notifyMyTypes<int>(void (tt)(int));
+template void Container::notifyMyTypes<int, double>(void (tt)(int, double));
+%}

Source/CParse/parser.y

@@ -5535,11 +5535,6 @@ declarator :  pointer notso_direct_declarator {
 	      $$.type = $1;
 	      SwigType_add_variadic($$.type);
            }
-           | ELLIPSIS direct_declarator {
-              $$ = $2;
-	      if (!$$.type) $$.type = NewStringEmpty();
-	      SwigType_add_variadic($$.type);
-           }
            | AND ELLIPSIS notso_direct_declarator {
 	     $$ = $3;
 	     $$.type = NewStringEmpty();
@@ -6170,6 +6165,10 @@ rawtype        : type_qualifier type_right {
 	          SwigType_push($$,$3);
 	          SwigType_push($$,$1);
 	       }
+	       | rawtype ELLIPSIS {
+		  $$ = $1;
+		  SwigType_add_variadic($$);
+	       }
                ;
 
 type_right     : primitive_type { $$ = $1;