[clang] [NFC][analyzer] Improve tracking of the current Block & LocCtx (PR #185107)

[Donát Nagy via cfe-commits]

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@@ -216,6 +216,14 @@ void CoreEngine::dispatchWorkItem(ExplodedNode *Pred, ProgramPoint Loc,
                              return timeTraceMetadata(Pred, Loc);
                            }};
   PrettyStackTraceLocationContext CrashInfo(Pred->getLocationContext());
+
+  // This work item is not necessarily related to the previous one, so
+  // the old current LocationContext and Block is no longer relevant.
+  // The new current LocationContext and Block should be set soon, but this
+  // guarantees that buggy access before that will trigger loud crashes instead
+  // of silently using stale data.
+  ExprEng.resetCurrLocationContextAndBlock();
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NagyDonat wrote:

My first impression was that this would be too paranoid, but on a second thought I actually like this suggestion. I'll add an assertion in `setCurrLocationContextAndBlock()`.

https://github.com/llvm/llvm-project/pull/185107