xref: /llvm-project/clang-tools-extra/clang-tidy/bugprone/BitwisePointerCastCheck.cpp (revision fb0ef6b66e3c7e91481568c15ed67c047dab84e1)
1 //===--- BitwisePointerCastCheck.cpp - clang-tidy -------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "BitwisePointerCastCheck.h"
10 #include "clang/ASTMatchers/ASTMatchFinder.h"
11 
12 using namespace clang::ast_matchers;
13 
14 namespace clang::tidy::bugprone {
15 
16 void BitwisePointerCastCheck::registerMatchers(MatchFinder *Finder) {
17   if (getLangOpts().CPlusPlus20) {
18     auto IsPointerType = refersToType(qualType(isAnyPointer()));
19     Finder->addMatcher(callExpr(hasDeclaration(functionDecl(allOf(
20                                     hasName("::std::bit_cast"),
21                                     hasTemplateArgument(0, IsPointerType),
22                                     hasTemplateArgument(1, IsPointerType)))))
23                            .bind("bit_cast"),
24                        this);
25   }
26 
27   auto IsDoublePointerType =
28       hasType(qualType(pointsTo(qualType(isAnyPointer()))));
29   Finder->addMatcher(callExpr(hasArgument(0, IsDoublePointerType),
30                               hasArgument(1, IsDoublePointerType),
31                               hasDeclaration(functionDecl(hasName("::memcpy"))))
32                          .bind("memcpy"),
33                      this);
34 }
35 
36 void BitwisePointerCastCheck::check(const MatchFinder::MatchResult &Result) {
37   if (const auto *Call = Result.Nodes.getNodeAs<CallExpr>("bit_cast"))
38     diag(Call->getBeginLoc(),
39          "do not use 'std::bit_cast' to cast between pointers")
40         << Call->getSourceRange();
41   else if (const auto *Call = Result.Nodes.getNodeAs<CallExpr>("memcpy"))
42     diag(Call->getBeginLoc(), "do not use 'memcpy' to cast between pointers")
43         << Call->getSourceRange();
44 }
45 
46 } // namespace clang::tidy::bugprone
47