[clang] [LifetimeSafety] Run analysis in post-order of CallGraph for better annotation propagation (PR #174178)

[Utkarsh Saxena via cfe-commits]

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@@ -2969,6 +3009,46 @@ void clang::sema::AnalysisBasedWarnings::IssueWarnings(
     CallableVisitor(CallAnalyzers, TU->getOwningModule())
         .TraverseTranslationUnitDecl(TU);
   }
+
+  if (S.getLangOpts().EnableLifetimeSafety && S.getLangOpts().CPlusPlus &&
+      S.getLangOpts().EnableLifetimeSafetyInferencePostOrder) {
+    llvm::SmallVector<const FunctionDecl *, 64> AllFunctions;
+    auto AddFunctionToList = [&](const Decl *D) -> void {
+      if (const auto *FD = dyn_cast<FunctionDecl>(D))
+        if (FD->doesThisDeclarationHaveABody() &&
+            !S.getSourceManager().isInSystemHeader(FD->getLocation()))
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usx95 wrote:

Why do we have to skip system headers ?

https://github.com/llvm/llvm-project/pull/174178