[clang] [llvm] [analyzer] Correct Z3 test cases, fix exposed crashes (PR #146597)

[Balazs Benics via llvm-commits]

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@@ -932,7 +932,8 @@ class Z3Statistics final : public SMTSolverStatistics {
   };
   unsigned getUnsigned(StringRef Key) const override {
     auto It = UnsignedValues.find(Key.str());
-    assert(It != UnsignedValues.end());
+    if (It == UnsignedValues.end())
+      return 0;
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steakhal wrote:

@vabridgers Could you investigate this question?

https://github.com/llvm/llvm-project/pull/146597