[PATCH] D59628: Add support for __attribute__((objc_class_stub))

John McCall via Phabricator via cfe-commits cfe-commits at lists.llvm.org
Tue Mar 26 15:38:48 PDT 2019


rjmccall added inline comments.


================
Comment at: lib/CodeGen/CGObjCMac.cpp:7274
+        // Classrefs pointing at Objective-C stub classes have the least
+        // significant bit set to 1.
+        auto *Tag = llvm::ConstantInt::get(CGM.IntPtrTy, 1);
----------------
slavapestov wrote:
> rjmccall wrote:
> > This isn't for an arbitrary class ref, it's for the global class list.  I'd say something like "the global class list sets the LSB to 1 on any class stubs".
> Can you explain what the difference is? My understanding is that the thing you pass to objc_loadClassref() (or load from directly) is a "classref". This is for classes you reference, not classes you define.
Oh, I see what you're saying, nevermind.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D59628/new/

https://reviews.llvm.org/D59628





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