[clang-tools-extra] [clangd] Harden incomingCalls() against possible misinterpretation of a range as pertaining to the wrong file (PR #111616)

[Haojian Wu via cfe-commits]

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@@ -2272,18 +2273,14 @@ incomingCalls(const CallHierarchyItem &Item, const SymbolIndex *Index) {
   // Initially store the ranges in a map keyed by SymbolID of the caller.
   // This allows us to group different calls with the same caller
   // into the same CallHierarchyIncomingCall.
-  llvm::DenseMap<SymbolID, std::vector<Range>> CallsIn;
+  llvm::DenseMap<SymbolID, std::vector<SymbolLocation>> CallsIn;
   // We can populate the ranges based on a refs request only. As we do so, we
   // also accumulate the container IDs into a lookup request.
   LookupRequest ContainerLookup;
   Index->refs(Request, [&](const Ref &R) {
-    auto Loc = indexToLSPLocation(R.Location, Item.uri.file());
-    if (!Loc) {
-      elog("incomingCalls failed to convert location: {0}", Loc.takeError());
-      return;
-    }
-    auto It = CallsIn.try_emplace(R.Container, std::vector<Range>{}).first;
-    It->second.push_back(Loc->range);
+    auto It =
+        CallsIn.try_emplace(R.Container, std::vector<SymbolLocation>{}).first;
+    It->second.push_back(R.Location);
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hokein wrote:

It seems we may introduce a use-after-free issue by storing the `SymbolLocation`, as the `FileURI` field is an unowned raw pointer. The callback result `R` is not guaranteed to remain valid outside of the callback context.

https://github.com/llvm/llvm-project/pull/111616