[clang] [clang][bytecode] Don't implicitly begin union member lifetime... (PR #192212)

[Vlad Serebrennikov via cfe-commits]

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@@ -5609,6 +5610,8 @@ bool Compiler<Emitter>::VisitCallExpr(const CallExpr *E) {
     assert(Args.size() == 2);
     IsAssignmentOperatorCall = true;
     std::reverse(Args.begin(), Args.end());
+    const CXXRecordDecl *LHSRecord = Args[0]->getType()->getAsCXXRecordDecl();
+    ActivateLHS = !LHSRecord || LHSRecord->hasTrivialDefaultConstructor();
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Endilll wrote:

Shouldn't this be
```suggestion
    ActivateLHS = LHSRecord && LHSRecord->hasTrivialDefaultConstructor();
```

If not, we need a test where `LHSRecord` is `nullptr`. I'm very curious how it would look like and why we should accept it.

https://github.com/llvm/llvm-project/pull/192212