[clang] [LifetimeSafety] Propagate loans through the GNU binary conditional (PR #204439)

[Gábor Horváth via cfe-commits]

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@@ -222,6 +222,12 @@ OriginList *OriginManager::getOrCreateList(const Expr *E) {
   if (const ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(E))
     return getOrCreateList(EWC->getSubExpr());
 
+  // An OpaqueValueExpr is a placeholder for an already-evaluated subexpression
+  // (e.g. the common operand of `a ?: b`); reuse its source's origins.
+  if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E))
+    if (const Expr *Src = OVE->getSourceExpr())
+      return getOrCreateList(Src);
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Xazax-hun wrote:

Oh my bad, now I remember why is it here. Just like with the `ExprWithCleanups` above, this does not show up in the CFG as an individual element. I could add a special case when we handle the binary conditional expression but I think it is more universal here (it also is impactful when this shows up at a different place).

https://github.com/llvm/llvm-project/pull/204439