blob: e2f61792a55aeada1f01aa34ec9fb091eac1dd57 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
// Warn about certain redundant casts:
//
// * A reinterpret_cast<T*>(...) whose result is then implicitly cast to a void
// pointer
//
// * A static_cast<T*>(e) where e is of void pointer type and whose result is
// then implicitly cast to a void pointer
//
// C-style casts are ignored because it makes this plugin simpler, and they
// should eventually be eliminated via loplugin:cstylecast and/or
// -Wold-style-cast. That implies that this plugin is only relevant for C++
// code.
#include "plugin.hxx"
namespace {
bool isVoidPointer(QualType type) {
return type->isPointerType()
&& type->getAs<PointerType>()->getPointeeType()->isVoidType();
}
class RedundantCast:
public RecursiveASTVisitor<RedundantCast>, public loplugin::Plugin
{
public:
explicit RedundantCast(InstantiationData const & data): Plugin(data) {}
virtual void run() override {
if (compiler.getLangOpts().CPlusPlus) {
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
}
bool VisitImplicitCastExpr(ImplicitCastExpr const * expr);
};
bool RedundantCast::VisitImplicitCastExpr(const ImplicitCastExpr * expr) {
if (ignoreLocation(expr) || expr->getCastKind() != CK_BitCast
|| !isVoidPointer(expr->getType())
|| !expr->getSubExpr()->getType()->isPointerType())
{
return true;
}
Expr const * e = expr->getSubExpr()->IgnoreParenImpCasts();
while (isa<CXXConstCastExpr>(e)) {
e = dyn_cast<CXXConstCastExpr>(e)->getSubExpr()->IgnoreParenImpCasts();
}
if (isa<CXXReinterpretCastExpr>(e)) {
report(
DiagnosticsEngine::Warning,
("redundant reinterpret_cast, result is implicitly cast to void"
" pointer"),
e->getExprLoc())
<< e->getSourceRange();
} else if (isa<CXXStaticCastExpr>(e)
&& isVoidPointer(
dyn_cast<CXXStaticCastExpr>(e)->getSubExpr()
->IgnoreParenImpCasts()->getType()))
{
report(
DiagnosticsEngine::Warning,
("redundant static_cast from void pointer, result is implicitly"
" cast to void pointer"),
e->getExprLoc())
<< e->getSourceRange();
}
return true;
}
loplugin::Plugin::Registration<RedundantCast> X("redundantcast");
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|
