[clang] [analyzer] Fix unary/binary op support for SMT symbolic execution (PR #205078)

[Balázs Benics via cfe-commits]

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@@ -242,6 +242,20 @@ const PointerToMemberData *BasicValueFactory::accumCXXBase(
   return getPointerToMemberData(ND, BaseSpecList);
 }
 
+std::optional<APSIntPtr> BasicValueFactory::evalAPSInt(UnaryOperator::Opcode Op,
+                                                       const llvm::APSInt &V1) {
+  switch (Op) {
+  default:
+    llvm_unreachable("Invalid Opcode.");
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steakhal wrote:

This definitely feels like a wrong choice here.
`evalAPSInt` should not invoke UB when passing non -,~ to it. It should just return nullopt - as the function signature would suggest, right?
btw, couldn't we also have unary `+`? Just like we have for explicit converting lambdas to function pointers?

https://github.com/llvm/llvm-project/pull/205078