[clang] [LifetimeSafety] Detect use-after-scope through fields in member calls (PR #191731)

[Utkarsh Saxena via cfe-commits]

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@@ -728,6 +728,38 @@ void FactsGenerator::handleInvalidatingCall(const Expr *Call,
         ThisList->getOuterOriginID(), Call));
 }
 
+void FactsGenerator::handleImplicitObjectFieldUses(const Expr *Call,
+                                                   const FunctionDecl *FD) {
+  const auto *MemberCall = dyn_cast_or_null<CXXMemberCallExpr>(Call);
+  if (!MemberCall)
+    return;
+
+  if (!isa_and_present<CXXThisExpr>(
+          MemberCall->getImplicitObjectArgument()->IgnoreImpCasts()))
+    return;
+
+  const auto *MD = dyn_cast<CXXMethodDecl>(FD);
+  assert(MD && "Expected MD to be a non-null pointer");
+
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usx95 wrote:

nit: change the assertion to mention why we expect that.

`assert(MD && "Function must be a CXXMethodDecl for member calls");`


https://github.com/llvm/llvm-project/pull/191731