Vendor import of clang release_39 branch r276489:vendor/clang/clang-release_39-r276489

https://llvm.org/svn/llvm-project/cfe/branches/release_39@276489

1 files changed, 52 insertions, 5 deletions

diff --git a/lib/Analysis/BodyFarm.cpp b/lib/Analysis/BodyFarm.cpp
index 09904369ba9c..d202a0406461 100644
--- a/lib/Analysis/BodyFarm.cpp
+++ b/lib/Analysis/BodyFarm.cpp
@@ -239,7 +239,8 @@ static Stmt *create_dispatch_once(ASTContext &C, const FunctionDecl *D) {
                                            SourceLocation());
   
   // (5) Create the 'if' statement.
-  IfStmt *If = new (C) IfStmt(C, SourceLocation(), nullptr, UO, CS);
+  IfStmt *If = new (C) IfStmt(C, SourceLocation(), false, nullptr, nullptr,
+                              UO, CS);
   return If;
 }
 
@@ -342,9 +343,8 @@ static Stmt *create_OSAtomicCompareAndSwap(ASTContext &C, const FunctionDecl *D)
   Stmt *Else = M.makeReturn(RetVal);
   
   /// Construct the If.
-  Stmt *If =
-    new (C) IfStmt(C, SourceLocation(), nullptr, Comparison, Body,
-                   SourceLocation(), Else);
+  Stmt *If = new (C) IfStmt(C, SourceLocation(), false, nullptr, nullptr,
+                            Comparison, Body, SourceLocation(), Else);
 
   return If;  
 }
@@ -383,10 +383,49 @@ Stmt *BodyFarm::getBody(const FunctionDecl *D) {
   return Val.getValue();
 }
 
+static const ObjCIvarDecl *findBackingIvar(const ObjCPropertyDecl *Prop) {
+  const ObjCIvarDecl *IVar = Prop->getPropertyIvarDecl();
+
+  if (IVar)
+    return IVar;
+
+  // When a readonly property is shadowed in a class extensions with a
+  // a readwrite property, the instance variable belongs to the shadowing
+  // property rather than the shadowed property. If there is no instance
+  // variable on a readonly property, check to see whether the property is
+  // shadowed and if so try to get the instance variable from shadowing
+  // property.
+  if (!Prop->isReadOnly())
+    return nullptr;
+
+  auto *Container = cast<ObjCContainerDecl>(Prop->getDeclContext());
+  const ObjCInterfaceDecl *PrimaryInterface = nullptr;
+  if (auto *InterfaceDecl = dyn_cast<ObjCInterfaceDecl>(Container)) {
+    PrimaryInterface = InterfaceDecl;
+  } else if (auto *CategoryDecl = dyn_cast<ObjCCategoryDecl>(Container)) {
+    PrimaryInterface = CategoryDecl->getClassInterface();
+  } else if (auto *ImplDecl = dyn_cast<ObjCImplDecl>(Container)) {
+    PrimaryInterface = ImplDecl->getClassInterface();
+  } else {
+    return nullptr;
+  }
+
+  // FindPropertyVisibleInPrimaryClass() looks first in class extensions, so it
+  // is guaranteed to find the shadowing property, if it exists, rather than
+  // the shadowed property.
+  auto *ShadowingProp = PrimaryInterface->FindPropertyVisibleInPrimaryClass(
+      Prop->getIdentifier(), Prop->getQueryKind());
+  if (ShadowingProp && ShadowingProp != Prop) {
+    IVar = ShadowingProp->getPropertyIvarDecl();
+  }
+
+  return IVar;
+}
+
 static Stmt *createObjCPropertyGetter(ASTContext &Ctx,
                                       const ObjCPropertyDecl *Prop) {
   // First, find the backing ivar.
-  const ObjCIvarDecl *IVar = Prop->getPropertyIvarDecl();
+  const ObjCIvarDecl *IVar = findBackingIvar(Prop);
   if (!IVar)
     return nullptr;
 
@@ -459,6 +498,14 @@ Stmt *BodyFarm::getBody(const ObjCMethodDecl *D) {
     return nullptr;
 
   // For now, we only synthesize getters.
+  // Synthesizing setters would cause false negatives in the
+  // RetainCountChecker because the method body would bind the parameter
+  // to an instance variable, causing it to escape. This would prevent
+  // warning in the following common scenario:
+  //
+  //  id foo = [[NSObject alloc] init];
+  //  self.foo = foo; // We should warn that foo leaks here.
+  //
   if (D->param_size() != 0)
     return nullptr;