donat.nagy added inline comments.
================ Comment at: clang/include/clang/Basic/AttrDocs.td:1189 +``onwership_returns``: Functions with this annotation return dynamic memory. +The second annotation parameter is the size of the returned memory in bytes. + ---------------- Szelethus wrote: > aaron.ballman wrote: > > I'm a bit confused on this last bit; how is the user supposed to statically > > know that value? I read this as claiming `my_malloc` returns 1 byte of > > dynamic storage; can the user tie the allocation to a parameter value > > instead? > I share your confusion, I guess. What I've written here is my best > understanding of how this works, unfortunately, these annotations were made > in ~2010 (when I was still in elementary school) and abandoned since. > > > I read this as claiming my_malloc returns 1 byte of dynamic storage; > > Thats what the corresponding code in the Static Analyzer leads me to believe > as well. > > > can the user tie the allocation to a parameter value instead? > > No. I'd guess that this annotation was designed for factory functions that construct an instance of a concrete struct type on the heap. Allowing "generic" malloc variants (where the allocation size is specified by a parameter) would be a good additional feature, but I think that the current annotation also has its own uses. Perhaps it would be good to provide examples like ``` void __attribute((ownership_takes(malloc, 1))) free_widget(struct widget *); struct widget *__attribute((ownership_returns(malloc, sizeof(struct widget)))) create_widget(void); void __attribute((ownership_holds(malloc, 1))) hold_widget(struct widget *); ``` that correspond to this use case. (By the way, does the checker handle non-`void*` pointers?) CHANGES SINCE LAST ACTION https://reviews.llvm.org/D156787/new/ https://reviews.llvm.org/D156787 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
