[clang] [clang] Diagnose dangling issues for the "Container<GSLPointer>" case. (PR #107213)

[Haojian Wu via cfe-commits]

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@@ -470,10 +474,24 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
         VisitGSLPointerArg(Callee, Args[0],
                            !Callee->getReturnType()->isReferenceType());
       } else {
-        if (auto *CCE = dyn_cast<CXXConstructExpr>(Call);
-            CCE && CCE->getConstructor()->getParent()->hasAttr<PointerAttr>())
-          VisitGSLPointerArg(CCE->getConstructor()->getParamDecl(0), Args[0],
-                             true);
+        if (auto *Ctor = dyn_cast<CXXConstructExpr>(Call)) {
+          const auto *ClassD = Ctor->getConstructor()->getParent();
+          // Constructing the Container<GSLPointer> case (e.g.
+          // std::optional<string_view>) case.
+          if (const auto *CTSD =
+                  dyn_cast<ClassTemplateSpecializationDecl>(ClassD)) {
+            if (isFirstTemplateArgumentGSLPointer(CTSD->getTemplateArgs()) &&
+                CTSD->hasAttr<OwnerAttr>()) {
+              VisitGSLPointerArg(Ctor->getConstructor()->getParamDecl(0),
+                                 Args[0], true);
+              return;
+            }
+          }
+          // Constructing the GSLPointer (e.g. std::string_view) case.
+          if (ClassD->hasAttr<PointerAttr>())
+            VisitGSLPointerArg(Ctor->getConstructor()->getParamDecl(0), Args[0],
+                               true);
+        }
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hokein wrote:

The logic here is tightly coupled with the lifetimebound attribute. If the first argument is already visited due to the lifetimebound attribute, we avoid performing the GSL analysis on it again to prevent duplication. Therefore, both checks need to remain within the same loop.

https://github.com/llvm/llvm-project/pull/107213