================ @@ -0,0 +1,75 @@ +//===----------------------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "RedundantZeroInitializerCheck.h" +#include "clang/AST/Decl.h" +#include "clang/AST/Expr.h" +#include "clang/AST/TypeLoc.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/ASTMatchers/ASTMatchers.h" +#include "clang/Basic/SourceManager.h" + +using namespace clang::ast_matchers; + +namespace clang::tidy::modernize { + +namespace { +// Matches an initializer list written as ``{<single element>}``. +AST_MATCHER(InitListExpr, isSingleElementBracedList) { + return Node.getLBraceLoc().isValid() && Node.getNumInits() == 1; +} +} // namespace + +void RedundantZeroInitializerCheck::registerMatchers(MatchFinder *Finder) { + Finder->addMatcher( + initListExpr( + hasType(constantArrayType()), isSingleElementBracedList(), + hasInit(0, ignoringParenImpCasts(integerLiteral(equals(0)))), + // Template instantiations share the pattern's written braces, + // so rewriting them could break a sibling instantiation. + unless(isInTemplateInstantiation()), + optionally(hasParent(varDecl().bind("var")))) + .bind("init"), + this); +} + +void RedundantZeroInitializerCheck::check( + const MatchFinder::MatchResult &Result) { + const auto *ILE = Result.Nodes.getNodeAs<InitListExpr>("init"); + + // In dependent template patterns the element type is unknown, so `{}` may not + // be equivalent to `{0}`. + if (ILE->isInstantiationDependent()) + return; + + // Skip arrays whose bound is deduced from the initializer (`T a[] = {0}`); + // there `{}` would deduce a different size than `{0}`. + if (const auto *Var = Result.Nodes.getNodeAs<VarDecl>("var")) + if (const TypeSourceInfo *TSI = Var->getTypeSourceInfo()) + if (const auto ATL = TSI->getTypeLoc().getAs<ArrayTypeLoc>()) + if (!ATL.getSizeExpr()) + return; + + const SourceRange Range = ILE->getSourceRange(); + if (Range.getBegin().isMacroID() || Range.getEnd().isMacroID()) + return; ---------------- zwuis wrote:
Move these to AST matchers like `isSingleElementBracedList`. https://github.com/llvm/llvm-project/pull/209367 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
