forked from OSchip/llvm-project
90 lines
3.5 KiB
C++
90 lines
3.5 KiB
C++
//===--- BoolPointerImplicitConversionCheck.cpp - clang-tidy --------------===//
|
|
//
|
|
// 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 "BoolPointerImplicitConversionCheck.h"
|
|
|
|
using namespace clang::ast_matchers;
|
|
|
|
namespace clang {
|
|
namespace tidy {
|
|
namespace bugprone {
|
|
|
|
void BoolPointerImplicitConversionCheck::registerMatchers(MatchFinder *Finder) {
|
|
// Look for ifs that have an implicit bool* to bool conversion in the
|
|
// condition. Filter negations.
|
|
Finder->addMatcher(
|
|
traverse(
|
|
TK_AsIs,
|
|
ifStmt(
|
|
hasCondition(findAll(implicitCastExpr(
|
|
unless(hasParent(unaryOperator(hasOperatorName("!")))),
|
|
hasSourceExpression(expr(
|
|
hasType(pointerType(pointee(booleanType()))),
|
|
ignoringParenImpCasts(anyOf(declRefExpr().bind("expr"),
|
|
memberExpr().bind("expr"))))),
|
|
hasCastKind(CK_PointerToBoolean)))),
|
|
unless(isInTemplateInstantiation()))
|
|
.bind("if")),
|
|
this);
|
|
}
|
|
|
|
static void checkImpl(const MatchFinder::MatchResult &Result, const Expr *Ref,
|
|
const IfStmt *If,
|
|
const ast_matchers::internal::Matcher<Expr> &RefMatcher,
|
|
ClangTidyCheck &Check) {
|
|
// Ignore macros.
|
|
if (Ref->getBeginLoc().isMacroID())
|
|
return;
|
|
|
|
// Only allow variable accesses and member exprs for now, no function calls.
|
|
// Check that we don't dereference the variable anywhere within the if. This
|
|
// avoids false positives for checks of the pointer for nullptr before it is
|
|
// dereferenced. If there is a dereferencing operator on this variable don't
|
|
// emit a diagnostic. Also ignore array subscripts.
|
|
if (!match(findAll(unaryOperator(hasOperatorName("*"),
|
|
hasUnaryOperand(RefMatcher))),
|
|
*If, *Result.Context)
|
|
.empty() ||
|
|
!match(findAll(arraySubscriptExpr(hasBase(RefMatcher))), *If,
|
|
*Result.Context)
|
|
.empty() ||
|
|
// FIXME: We should still warn if the paremater is implicitly converted to
|
|
// bool.
|
|
!match(
|
|
findAll(callExpr(hasAnyArgument(ignoringParenImpCasts(RefMatcher)))),
|
|
*If, *Result.Context)
|
|
.empty() ||
|
|
!match(
|
|
findAll(cxxDeleteExpr(has(ignoringParenImpCasts(expr(RefMatcher))))),
|
|
*If, *Result.Context)
|
|
.empty())
|
|
return;
|
|
|
|
Check.diag(Ref->getBeginLoc(),
|
|
"dubious check of 'bool *' against 'nullptr', did "
|
|
"you mean to dereference it?")
|
|
<< FixItHint::CreateInsertion(Ref->getBeginLoc(), "*");
|
|
}
|
|
|
|
void BoolPointerImplicitConversionCheck::check(
|
|
const MatchFinder::MatchResult &Result) {
|
|
const auto *If = Result.Nodes.getNodeAs<IfStmt>("if");
|
|
if (const auto *E = Result.Nodes.getNodeAs<Expr>("expr")) {
|
|
const Decl *D = isa<DeclRefExpr>(E) ? cast<DeclRefExpr>(E)->getDecl()
|
|
: cast<MemberExpr>(E)->getMemberDecl();
|
|
const auto M =
|
|
ignoringParenImpCasts(anyOf(declRefExpr(to(equalsNode(D))),
|
|
memberExpr(hasDeclaration(equalsNode(D)))));
|
|
checkImpl(Result, E, If, M, *this);
|
|
}
|
|
}
|
|
|
|
} // namespace bugprone
|
|
} // namespace tidy
|
|
} // namespace clang
|