llvm-project

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//===--- DynamicStaticInitializersCheck.cpp - clang-tidy ------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "DynamicStaticInitializersCheck.h"
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#include "../utils/FileExtensionsUtils.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/ASTMatchers/ASTMatchFinder.h"
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using namespace clang::ast_matchers;
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namespace clang::tidy::bugprone {
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AST_MATCHER(clang::VarDecl, hasConstantDeclaration) {
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  const Expr *Init = Node.getInit();
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  if (Init && !Init->isValueDependent()) {
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    if (Node.isConstexpr())
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      return true;
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    return Node.evaluateValue();
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  }
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  return false;
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}
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DynamicStaticInitializersCheck::DynamicStaticInitializersCheck(
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    StringRef Name, ClangTidyContext *Context)
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    : ClangTidyCheck(Name, Context),
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      HeaderFileExtensions(Context->getHeaderFileExtensions()) {}
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void DynamicStaticInitializersCheck::registerMatchers(MatchFinder *Finder) {
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  Finder->addMatcher(
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      varDecl(hasGlobalStorage(), unless(hasConstantDeclaration())).bind("var"),
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      this);
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}
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void DynamicStaticInitializersCheck::check(const MatchFinder::MatchResult &Result) {
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  const auto *Var = Result.Nodes.getNodeAs<VarDecl>("var");
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  SourceLocation Loc = Var->getLocation();
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  if (!Loc.isValid() || !utils::isPresumedLocInHeaderFile(Loc, *Result.SourceManager,
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                                                          HeaderFileExtensions))
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    return;
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  // If the initializer is a constant expression, then the compiler
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  // doesn't have to dynamically initialize it.
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  diag(Loc, "static variable %0 may be dynamically initialized in this header file")
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    << Var;
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}
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} // namespace clang::tidy::bugprone
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