fix: remove f1 flag, cleanup problematic declarations correctly

docs/faq.rst

@@ -98,6 +98,9 @@ Currently this adds the support for elaborated type specifiers.
 \_\_va_list_tag and other hidden declarations (f1)
 --------------------------------------------------
 
+!!! This flag has been removed from pygccxml > 2.6
+We will now always remove these declarations
+
 When parsing with CastXML, the XML tree can contain declarations named
 ``__va_list_tag``. If the compiler is llvm 3.9,  ``__NSConstantString_tag``
 and ``__NSConstantString`` declarations may also be present.

src/pygccxml/parser/scanner.py

@@ -197,6 +197,15 @@ def __init__(self, xml_file, decl_factory, config, *args):
             "__vr_offs",
         ]
 
+        # With CastXML and clang some __va_list_tag declarations are
+        # present in the tree
+        # With llvm 3.9 there is a __NSConstantString(_tag) in the tree
+        self.__declarations_to_skip = [
+            "__va_list_tag",
+            "__NSConstantString_tag",
+            "__NSConstantString"
+        ]
+
         self.__xml_generator_from_xml_file = None
 
     @property
@@ -297,21 +306,10 @@ def startElement(self, name, attrs):
             self.__read_access(attrs)
             element_id = attrs.get(XML_AN_ID)
 
-            # With CastXML and clang some __va_list_tag declarations are
-            # present in the tree: we do not want to have these in the tree.
-            # With llvm 3.9 there is a __NSConstantString(_tag) in the tree
-            # We hide these declarations by default
-            rm1 = "f1" not in self.config.flags
-            names = [
-                "__va_list_tag",
-                "__NSConstantString_tag",
-                "__NSConstantString"]
-
             if isinstance(obj, declarations.declaration_t):
 
-                if rm1 and str(obj.name) in names:
+                if obj.name in self.__declarations_to_skip:
                     return
-
                 self.__update_membership(attrs)
                 self.__declarations[element_id] = obj
                 if not isinstance(obj, declarations.namespace_t):