clang-tools 8.0.0

MultipleStatementMacroCheck.cpp
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1 //===--- MultipleStatementMacroCheck.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
10 #include "MultipleStatementMacroCheck.h"
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 bugprone {
19
20 namespace {
21
22 AST_MATCHER(Expr, isInMacro) { return Node.getBeginLoc().isMacroID(); }
23
24 /// \brief Find the next statement after `S`.
25 const Stmt *nextStmt(const MatchFinder::MatchResult &Result, const Stmt *S) {
26 auto Parents = Result.Context->getParents(*S);
27 if (Parents.empty())
28 return nullptr;
29 const auto *Parent = Parents[0].get<Stmt>();
30 if (!Parent)
31 return nullptr;
32 const Stmt *Prev = nullptr;
33 for (const Stmt *Child : Parent->children()) {
34 if (Prev == S)
35 return Child;
36 Prev = Child;
37 }
38 return nextStmt(Result, Parent);
39 }
40
41 using ExpansionRanges = std::vector<SourceRange>;
42
43 /// \bried Get all the macro expansion ranges related to `Loc`.
44 ///
45 /// The result is ordered from most inner to most outer.
46 ExpansionRanges getExpansionRanges(SourceLocation Loc,
47 const MatchFinder::MatchResult &Result) {
48 ExpansionRanges Locs;
49 while (Loc.isMacroID()) {
50 Locs.push_back(
51 Result.SourceManager->getImmediateExpansionRange(Loc).getAsRange());
52 Loc = Locs.back().getBegin();
53 }
54 return Locs;
55 }
56
57 } // namespace
58
59 void MultipleStatementMacroCheck::registerMatchers(MatchFinder *Finder) {
60 const auto Inner = expr(isInMacro(), unless(compoundStmt())).bind("inner");
61 Finder->addMatcher(
62 stmt(anyOf(ifStmt(hasThen(Inner)), ifStmt(hasElse(Inner)).bind("else"),
63 whileStmt(hasBody(Inner)), forStmt(hasBody(Inner))))
64 .bind("outer"),
65 this);
66 }
67
68 void MultipleStatementMacroCheck::check(
69 const MatchFinder::MatchResult &Result) {
70 const auto *Inner = Result.Nodes.getNodeAs<Expr>("inner");
71 const auto *Outer = Result.Nodes.getNodeAs<Stmt>("outer");
72 const auto *Next = nextStmt(Result, Outer);
73 if (!Next)
74 return;
75
76 SourceLocation OuterLoc = Outer->getBeginLoc();
77 if (Result.Nodes.getNodeAs<Stmt>("else"))
78 OuterLoc = cast<IfStmt>(Outer)->getElseLoc();
79
80 auto InnerRanges = getExpansionRanges(Inner->getBeginLoc(), Result);
81 auto OuterRanges = getExpansionRanges(OuterLoc, Result);
82 auto NextRanges = getExpansionRanges(Next->getBeginLoc(), Result);
83
84 // Remove all the common ranges, starting from the top (the last ones in the
85 // list).
86 while (!InnerRanges.empty() && !OuterRanges.empty() && !NextRanges.empty() &&
87 InnerRanges.back() == OuterRanges.back() &&
88 InnerRanges.back() == NextRanges.back()) {
89 InnerRanges.pop_back();
90 OuterRanges.pop_back();
91 NextRanges.pop_back();
92 }
93
94 // Inner and Next must have at least one more macro that Outer doesn't have,
95 // and that range must be common to both.
96 if (InnerRanges.empty() || NextRanges.empty() ||
97 InnerRanges.back() != NextRanges.back())
98 return;
99
100 diag(InnerRanges.back().getBegin(), "multiple statement macro used without "
101 "braces; some statements will be "
102 "unconditionally executed");
103 }
104
105 } // namespace bugprone
106 } // namespace tidy
107 } // namespace clang
Loc
SourceLocation Loc
&#39;#&#39; location in the include directive
Definition: IncludeOrderCheck.cpp:37
clang::ast_matchers
Definition: AbseilMatcher.h:15
clang::tidy::matchers::AST_MATCHER
AST_MATCHER(BinaryOperator, isAssignmentOperator)
Definition: Matchers.h:20
MultipleStatementMacroCheck.h
Result
llvm::Optional< llvm::Expected< tooling::AtomicChanges > > Result
Definition: ClangdServer.cpp:60
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ChangeNamespace.cpp:18