[NFC] Add release notes and address review comments

Signed-off-by: yronglin <[email protected]>

Author: yronglin

clang/docs/ReleaseNotes.rst

@@ -216,6 +216,10 @@ Code Completion
 Static Analyzer
 ---------------
 
+- Clang currently support extending lifetime of object bound to 
+  reference members of aggregates in CFG and ExprEngine, that are
+  created from default member initializer.
+
 New features
 ^^^^^^^^^^^^
 

clang/lib/Analysis/ReachableCode.cpp

@@ -457,7 +457,7 @@ bool DeadCodeScan::isDeadCodeRoot(const clang::CFGBlock *Block) {
 // Check if the given `DeadStmt` is one of target statements or is a sub-stmt of
 // them. `Block` is the CFGBlock containing the `DeadStmt`.
 template <class... Ts>
-static bool isDeadSubStmtInOneOf(const Stmt *DeadStmt, const CFGBlock *Block) {
+static bool isDeadStmtInOneOf(const Stmt *DeadStmt, const CFGBlock *Block) {
   // The coroutine statement, co_return, co_await, or co_yield.
   const Stmt *TargetStmt = nullptr;
   // Find the first coroutine statement after the DeadStmt in the block.
@@ -503,8 +503,8 @@ static bool isValidDeadStmt(const Stmt *S, const clang::CFGBlock *Block) {
   // If the dead stmt is a sub-stmt of CXXDefaultInitExpr and CXXDefaultArgExpr,
   // we would rather expect to find CXXDefaultInitExpr and CXXDefaultArgExpr as
   // a valid dead stmt.
-  return !isDeadSubStmtInOneOf<CoreturnStmt, CoroutineSuspendExpr,
-                               CXXDefaultArgExpr, CXXDefaultInitExpr>(S, Block);
+  return !isDeadStmtInOneOf<CoreturnStmt, CoroutineSuspendExpr,
+                            CXXDefaultArgExpr, CXXDefaultInitExpr>(S, Block);
 }
 
 const Stmt *DeadCodeScan::findDeadCode(const clang::CFGBlock *Block) {

clang/lib/Sema/SemaExpr.cpp

@@ -5570,7 +5570,7 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
           /*SkipImmediateInvocations=*/NestedDefaultChecking))
     return ExprError();
 
-  Expr *RewrittenExpr = Init == Param->getDefaultArg() ? nullptr : Init;
+  Expr *RewrittenExpr = (Init == Param->getDefaultArg() ? nullptr : Init);
   return CXXDefaultArgExpr::Create(Context, InitializationContext->Loc, Param,
                                    RewrittenExpr,
                                    InitializationContext->Context);

clang/test/Analysis/lifetime-extended-regions.cpp

@@ -121,7 +121,7 @@ void aggregateWithReferences() {
   clang_analyzer_dump(viaReference.rx); // expected-warning-re {{&lifetime_extended_object{int, viaReference, S{{[0-9]+}}} }}
   clang_analyzer_dump(viaReference.ry); // expected-warning-re {{&lifetime_extended_object{Composite, viaReference, S{{[0-9]+}}} }}
 
-  // The lifetime lifetime of object bound to reference members of aggregates,
+  // The lifetime of object bound to reference members of aggregates,
   // that are created from default member initializer was extended.
   RefAggregate defaultInitExtended{i};
   clang_analyzer_dump(defaultInitExtended.ry); // expected-warning-re {{&lifetime_extended_object{Composite, defaultInitExtended, S{{[0-9]+}}} }}