[Lldb-commits] [lldb] [LLDB] Fix crash in TypeSystemClang::GetIndexofChildMemberWithName. (PR #117808)

[Pavel Labath via lldb-commits]

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@@ -6754,12 +6754,12 @@ size_t TypeSystemClang::GetIndexOfChildMemberWithName(
           llvm::StringRef field_name = field->getName();
           if (field_name.empty()) {
             CompilerType field_type = GetType(field->getType());
+            std::vector<uint32_t> save_indices = child_indexes;
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labath wrote:

So, my preferred solution would be to have this function return a `vector<int>` (apparently, there's even a TODO in the header about that (*)). That way you can build the result from the bottom up, and only add things to the vector when you've found the thing you're searching for and are certain that you're going to return successfully. That's going to be slightly slower than passing the same vector always (but maybe not slower than making a copy of it preemptively). However, I can live with both yours and Michael's solution (which I think could still work if you keep the `pop_back` statement so that the next iteration starts with a valid state). I'll leave it up to Michael to decide, as he spends most of the time looking at this code.

(*) Technically the TODO is about returning a `vector<vector<int>>` of all possible matches --  which may be a good idea overall, but I don't think we want to do that now.

https://github.com/llvm/llvm-project/pull/117808