clang-tools  7.0.0
InterfacesGlobalInitCheck.cpp
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1 //===--- InterfacesGlobalInitCheck.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 InterfacesGlobalInitCheck::registerMatchers(MatchFinder *Finder) {
21  const auto IsGlobal =
22  allOf(hasGlobalStorage(),
23  hasDeclContext(anyOf(translationUnitDecl(), // Global scope.
24  namespaceDecl(), // Namespace scope.
25  recordDecl())), // Class scope.
26  unless(isConstexpr()));
27 
28  const auto ReferencesUndefinedGlobalVar = declRefExpr(hasDeclaration(
29  varDecl(IsGlobal, unless(isDefinition())).bind("referencee")));
30 
31  Finder->addMatcher(
32  varDecl(IsGlobal, isDefinition(),
33  hasInitializer(expr(hasDescendant(ReferencesUndefinedGlobalVar))))
34  .bind("var"),
35  this);
36 }
37 
38 void InterfacesGlobalInitCheck::check(const MatchFinder::MatchResult &Result) {
39  const auto *const Var = Result.Nodes.getNodeAs<VarDecl>("var");
40  // For now assume that people who write macros know what they're doing.
41  if (Var->getLocation().isMacroID())
42  return;
43  const auto *const Referencee = Result.Nodes.getNodeAs<VarDecl>("referencee");
44  // If the variable has been defined, we're good.
45  const auto *const ReferenceeDef = Referencee->getDefinition();
46  if (ReferenceeDef != nullptr &&
47  Result.SourceManager->isBeforeInTranslationUnit(
48  ReferenceeDef->getLocation(), Var->getLocation())) {
49  return;
50  }
51  diag(Var->getLocation(),
52  "initializing non-local variable with non-const expression depending on "
53  "uninitialized non-local variable %0")
54  << Referencee;
55 }
56 
57 } // namespace cppcoreguidelines
58 } // namespace tidy
59 } // namespace clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//