vsk added inline comments.
================ Comment at: lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libcxx/string/main.cpp:29 + if (sizeof(std::string) == sizeof(garbage_string_sso)) + memcpy((void *)&garbage1, &garbage_string_sso, sizeof(std::string)); + if (sizeof(std::string) == sizeof(garbage_string_long)) ---------------- shafik wrote: > While I get what you are doing here, we know he structure of libc++ SSO > implementation and we are manually building a corrupt one, this is fragile to > changes in the implementation. > > I don't have an immediate suggestion for an alternative approach but if we > stick with this we should stick a big comment explaining this, perhaps laying > out the assumptions of the internal layout we are assuming and maybe some > sanity checks maybe using `offsetof` to verify fields exist and are where we > expect them to be. I don't see how this is fragile. The structure of libc++'s SSO implementation is ABI, and is unlikely to change (esp. not in a way that turns either one of the garbage strings into a valid string). I've left comments explaining what's wrong with both of the garbage strings, but can leave a pointer to https://joellaity.com/2020/01/31/string.html for more info? ================ Comment at: lldb/source/DataFormatters/StringPrinter.cpp:64 +static bool isInHalfOpenRange(uint8_t *Needle, uint8_t *Start, uint8_t *End) { + return uintptr_t(Needle) >= uintptr_t(Start) && + uintptr_t(Needle) < uintptr_t(End); ---------------- shafik wrote: > can we use `reinterpret_cast` as opposed to what is basically a C-style cast. > This also has the advantage of pointing out potentially dangerous code for > future persons refactoring this code. As written, I think the casts to `uintptr_t` convey the assumptions being made here. CHANGES SINCE LAST ACTION https://reviews.llvm.org/D73860/new/ https://reviews.llvm.org/D73860 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
