[clang-tidy] Use hasLocalStorage() to identify unnecessary copy initializations to exclude static local variables.

Summary: Since local static variables can outlive other local variables exclude them from the unnecessary copy initialization check.

Reviewers: alexfh

Patch by Felix Berger!

Differential Revision: http://reviews.llvm.org/D15822

llvm-svn: 256636

clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp

@@ -19,7 +19,6 @@ namespace performance {
 using namespace ::clang::ast_matchers;
 
 namespace {
-AST_MATCHER(VarDecl, isLocalVarDecl) { return Node.isLocalVarDecl(); }
 AST_MATCHER(QualType, isPointerType) { return Node->isPointerType(); }
 } // namespace
 
@@ -43,7 +42,7 @@ void UnnecessaryCopyInitialization::registerMatchers(
                unless(callee(cxxMethodDecl())));
   Finder->addMatcher(
       varDecl(
-          isLocalVarDecl(), hasType(isConstQualified()),
+          hasLocalStorage(), hasType(isConstQualified()),
           hasType(matchers::isExpensiveToCopy()),
           hasInitializer(cxxConstructExpr(
               hasDeclaration(cxxConstructorDecl(isCopyConstructor())),

clang-tools-extra/test/clang-tidy/performance-unnecessary-copy-initialization.cpp

@@ -110,6 +110,10 @@ void NegativeFunctionCallTrivialType() {
   const TrivialToCopyType VarCopyConstructed(TrivialTypeReference());
 }
 
+void NegativeStaticLocalVar(const ExpensiveToCopyType &Obj) {
+  static const auto StaticVar = Obj.reference();
+}
+
 void NegativeFunctionCallExpensiveTypeNonConstVariable() {
   auto AutoAssigned = ExpensiveTypeReference();
   auto AutoCopyConstructed(ExpensiveTypeReference());