clang-tools  7.0.0
ProTypeStaticCastDowncastCheck.cpp
Go to the documentation of this file.
1 //===--- ProTypeStaticCastDowncastCheck.cpp - clang-tidy-------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 
14 using namespace clang::ast_matchers;
15 
16 namespace clang {
17 namespace tidy {
18 namespace cppcoreguidelines {
19 
20 void ProTypeStaticCastDowncastCheck::registerMatchers(MatchFinder *Finder) {
21  if (!getLangOpts().CPlusPlus)
22  return;
23 
24  Finder->addMatcher(
25  cxxStaticCastExpr(unless(isInTemplateInstantiation())).bind("cast"),
26  this);
27 }
28 
29 void ProTypeStaticCastDowncastCheck::check(
30  const MatchFinder::MatchResult &Result) {
31  const auto *MatchedCast = Result.Nodes.getNodeAs<CXXStaticCastExpr>("cast");
32  if (MatchedCast->getCastKind() != CK_BaseToDerived)
33  return;
34 
35  QualType SourceType = MatchedCast->getSubExpr()->getType();
36  const auto *SourceDecl = SourceType->getPointeeCXXRecordDecl();
37  if (!SourceDecl) // The cast is from object to reference
38  SourceDecl = SourceType->getAsCXXRecordDecl();
39  if (!SourceDecl)
40  return;
41 
42  if (SourceDecl->isPolymorphic())
43  diag(MatchedCast->getOperatorLoc(),
44  "do not use static_cast to downcast from a base to a derived class; "
45  "use dynamic_cast instead")
46  << FixItHint::CreateReplacement(MatchedCast->getOperatorLoc(),
47  "dynamic_cast");
48  else
49  diag(MatchedCast->getOperatorLoc(),
50  "do not use static_cast to downcast from a base to a derived class");
51 }
52 
53 } // namespace cppcoreguidelines
54 } // namespace tidy
55 } // namespace clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//