[cfe-dev] [Patch] IDNS_NoLookup?
dgregor at apple.com
Sun Jan 18 19:02:58 CST 2009
On Jan 14, 2009, at 12:17 PM, Piotr Rak wrote:
> I would like to introduce new identifier namespace, which would cause
> ScopedDecl not be added to DeclContext lookup structure. Currently it
> IdentifierResolver saves us somehow from building lookup structure for
> TranslationUnit, however, as i mentioned few weeks earlier I store
> using-directives in lookup structure. This causes it to be build for
> TranslationUnitDecl too in my local copy.
using-directives won't have names, right? So it doesn't really matter
that they won't have any identifier namespace defined for them.
> This fails for
> ObjCImplementation (there might be more somewhere in ObjC code, not
> really sure...), which has associated name but getIdentifierNamespace
> is not defined for it. I could probably workaround it, but this way
> feels `less hackish`. Please note that this change also saves from
> crash client code, that would call TranslationUnitDecl::lookup(), when
> it owns ObjCImplementationDecls.
Ah, so that's the issue... the ObjCImplementationDecls need to have an
identifier namespace, because they have name, but they aren't
supposed to be found by name lookup (rather, we see them through the
Adding another namespace will work, but I don't know if it's the best
answer. Perhaps what we really mean is that ObjCImplementationDecls
really don't have names at all: they're just unnamed entities that
attach to other entities, and the only reason they have a name in the
source code is to tie them to the appropriate interface:
@implementation Blah /* ties this ObjCImplementationDecl to the
ObjCInterfaceDecl above */
One could certainly ask an ObjCImplementationDecl what the name of its
corresponding interface is, through a separate operation, even though
the ObjCImplementationDecl itself is unnamed.
I'm not quite sure which way to go with this. IDNS_NoLookup works, but
I think an unnamed ObjCImplementationDecl will be better. Let's see if
someone with a better understanding of Objective-C semantics can chime
in to see if my understanding of ObjCImplementationDecl is reasonable.
More information about the cfe-dev