[clang] [clang] Introduce [[clang::lifetime_capture_by(X)]] (PR #111499)

[Haojian Wu via cfe-commits]

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@@ -269,6 +271,40 @@ void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
   }
 }
 
+static bool IsPointerLikeType(QualType QT) {
+  QT = QT.getNonReferenceType();
+  // if (QT->isPointerType())
+  //   return true;
+  auto *RD = QT->getAsCXXRecordDecl();
+  if (!RD)
+    return false;
+  RD = RD->getCanonicalDecl();
+  if (auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(RD))
+    RD = CTSD->getSpecializedTemplate()->getTemplatedDecl();
+  return RD->hasAttr<PointerAttr>();
+}
+
+void Sema::inferLifetimeCaptureByAttribute(FunctionDecl *FD) {
+  if (!FD)
+    return;
+  auto *MD = dyn_cast<CXXMethodDecl>(FD);
+  if (!MD || !MD->getIdentifier() || !MD->getParent()->isInStdNamespace())
+    return;
+  static const llvm::StringSet<> CapturingMethods{"insert", "push",
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hokein wrote:

I think the `[]` operator for map-like container is an important case, code like below is probably not rare:

```
std::map<string_view, ...> m;
m[ReturnString(..)] = ...; // this leaves a dangling string_view key in the map.
``` 

https://github.com/llvm/llvm-project/pull/111499