do not modify warning-flags.c

Author: evelez7

clang/include/clang/Basic/DiagnosticParseKinds.td

@@ -887,9 +887,10 @@ def err_requires_expr_in_simple_requirement : Error<
   "requires expression in requirement body; did "
   "you intend to place it in a nested requirement? (add another 'requires' "
   "before the expression)">;
-def warn_missing_template_arg_list_after_template_kw : Warning<
+def missing_template_arg_list_after_template_kw : Extension<
   "a template argument list is expected after a name prefixed by the template "
-  "keyword">, InGroup<Pedantic>, DefaultError;
+  "keyword">, InGroup<DiagGroup<"missing-template-arg-list-after-template-kw">>, 
+  DefaultError;
 
 def err_missing_dependent_template_keyword : Error<
   "use 'template' keyword to treat '%0' as a dependent template name">;

clang/lib/Parse/ParseExprCXX.cpp

@@ -3042,7 +3042,7 @@ bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, ParsedType ObjectType,
       if ((TNK == TNK_Function_template || TNK == TNK_Dependent_template_name ||
            TNK == TNK_Var_template) &&
           !Tok.is(tok::less))
-        Diag(IdLoc, diag::warn_missing_template_arg_list_after_template_kw);
+        Diag(IdLoc, diag::missing_template_arg_list_after_template_kw);
     }
     return false;
   }

clang/test/Misc/warning-flags.c

@@ -89,4 +89,4 @@ CHECK-NEXT:   warn_weak_import
 
 The list of warnings in -Wpedantic should NEVER grow.
 
-CHECK: Number in -Wpedantic (not covered by other -W flags): 27
+CHECK: Number in -Wpedantic (not covered by other -W flags): 26