[Lldb-commits] [PATCH] D145276: [lldb] Let 'v' command directly access ivars of _any_ self/this

[Dave Lee via Phabricator via lldb-commits]

kastiglione added inline comments.


================
Comment at: lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:9818
+    if (ClangASTMetadata *metadata = GetMetadata(fun_decl))
+      return metadata->GetObjectPtrLanguage();
+  }
----------------
kastiglione wrote:
> aprantl wrote:
> > Couple of questions for my understanding:
> > 
> > 1. Do you see any opportunities for this to spectacularly do the wrong thing in an ObjectiveC++ program by guessing the wrong language? I suppose this just tries to do a best effort?
> > 
> > 2. We're not using the DW_AT_APPLE_runtime_language attribute because it's only attached to Objective-C classes?
> > 
> > 3. We're not using the DW_AT_language of the DW_TAG_compile_unit because it won't help us in an ObjC++ program?
> > We're not using the `DW_AT_APPLE_runtime_language` attribute because it's only attached to Objective-C classes?
> > We're not using the `DW_AT_language` of the `DW_TAG_compile_unit` because it won't help us in an ObjC++ program?
> 
> I am not sure how to answer these too. While this function is new, the logic and this code path which calls `GetObjectPtrLanguage`, is taken from the existing implementation. In other words, how the debug info is made use of, hasn't changed.
> Do you see any opportunities for this to spectacularly do the wrong thing in an ObjectiveC++ program by guessing the wrong language? I suppose this just tries to do a best effort?

I don't see any obvious ways to get it wrong, but can't rule it out entirely. The way this change is implemented, there should be no way to have a regression – everything that used to work should still work. There could be some case out there where, in objc++, the wrong choice is made between `this`/`self`, but that would result in the same "variable not found" message you'd get today in that case (since the implementation should have no regressions).


Repository:
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  https://reviews.llvm.org/D145276/new/

https://reviews.llvm.org/D145276