Add more tests, and a minor fix for a function returning gsl pointer.

Author: hokein

clang/lib/Sema/CheckExprLifetime.cpp

@@ -1179,8 +1179,8 @@ static AnalysisResult analyzePathForGSLPointer(const IndirectLocalPath &Path,
   //    const std::string& Ref(const std::string& a [[clang::lifetimebound]]);
   //    string_view abc = Ref(std::string());
   // The "Path" is [GSLPointerInit, LifetimeboundCall], where "L" is the
-  // temporary "std::string()" object. We need to check if the function with the
-  // lifetimebound attribute returns a "owner" type.
+  // temporary "std::string()" object. We need to check the return type of the
+  // function with the lifetimebound attribute.
   if (Path.back().Kind == IndirectLocalPathEntry::LifetimeBoundCall) {
     // The lifetimebound applies to the implicit object parameter of a method.
     const FunctionDecl *FD =
@@ -1195,10 +1195,13 @@ static AnalysisResult analyzePathForGSLPointer(const IndirectLocalPath &Path,
       // We still respect this case even the type S is not an owner.
       return Report;
     }
-    // Check if the return type has an Owner attribute.
-    //   e.g., const GSLOwner& func(const Foo& foo [[clang::lifetimebound]])
-    if (FD && FD->getReturnType()->isReferenceType() &&
-        isRecordWithAttr<OwnerAttr>(FD->getReturnType()->getPointeeType()))
+    // Check the return type, e.g.
+    //   const GSLOwner& func(const Foo& foo [[clang::lifetimebound]])
+    //   GSLPointer func(const Foo& foo [[clang::lifetimebound]])
+    if (FD &&
+        ((FD->getReturnType()->isReferenceType() &&
+          isRecordWithAttr<OwnerAttr>(FD->getReturnType()->getPointeeType())) ||
+         isRecordWithAttr<PointerAttr>(FD->getReturnType())))
       return Report;
 
     return Abandon;

clang/test/Sema/warn-lifetime-analysis-nocfg.cpp

@@ -698,10 +698,28 @@ void test() {
 namespace LifetimeboundInterleave {
 
 const std::string& Ref(const std::string& abc [[clang::lifetimebound]]);
+
+std::string_view TakeSv(std::string_view abc [[clang::lifetimebound]]);
+std::string_view TakeStrRef(const std::string& abc [[clang::lifetimebound]]);
+std::string_view TakeStr(std::string abc [[clang::lifetimebound]]);
+
 std::string_view test1() {
   std::string_view t1 = Ref(std::string()); // expected-warning {{object backing}}
   t1 = Ref(std::string()); // expected-warning {{object backing}}
   return Ref(std::string()); // expected-warning {{returning address}}
+  
+  std::string_view t2 = TakeSv(std::string()); // expected-warning {{object backing}}
+  t2 = TakeSv(std::string()); // expected-warning {{object backing}}
+  return TakeSv(std::string()); // expected-warning {{returning address}}
+
+  std::string_view t3 = TakeStrRef(std::string()); // expected-warning {{temporary}}
+  t3 = TakeStrRef(std::string()); // expected-warning {{object backing}}
+  return TakeStrRef(std::string()); // expected-warning {{returning address}}
+
+
+  std::string_view t4 = TakeStr(std::string());
+  t4 = TakeStr(std::string());
+  return TakeStr(std::string());
 }
 
 template <typename T>