xref: /llvm-project/clang-tools-extra/clang-tidy/bugprone/DynamicStaticInitializersCheck.cpp (revision 11a411a49b62c129bba551df4587dd446fcdc660)
1 //===--- DynamicStaticInitializersCheck.cpp - clang-tidy ------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "DynamicStaticInitializersCheck.h"
10 #include "../utils/FileExtensionsUtils.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 
14 using namespace clang::ast_matchers;
15 
16 namespace clang::tidy::bugprone {
17 
AST_MATCHER(clang::VarDecl,hasConstantDeclaration)18 AST_MATCHER(clang::VarDecl, hasConstantDeclaration) {
19   const Expr *Init = Node.getInit();
20   if (Init && !Init->isValueDependent()) {
21     if (Node.isConstexpr())
22       return true;
23     return Node.evaluateValue();
24   }
25   return false;
26 }
27 
DynamicStaticInitializersCheck(StringRef Name,ClangTidyContext * Context)28 DynamicStaticInitializersCheck::DynamicStaticInitializersCheck(
29     StringRef Name, ClangTidyContext *Context)
30     : ClangTidyCheck(Name, Context),
31       HeaderFileExtensions(Context->getHeaderFileExtensions()) {}
32 
registerMatchers(MatchFinder * Finder)33 void DynamicStaticInitializersCheck::registerMatchers(MatchFinder *Finder) {
34   Finder->addMatcher(
35       varDecl(hasGlobalStorage(), unless(hasConstantDeclaration())).bind("var"),
36       this);
37 }
38 
check(const MatchFinder::MatchResult & Result)39 void DynamicStaticInitializersCheck::check(const MatchFinder::MatchResult &Result) {
40   const auto *Var = Result.Nodes.getNodeAs<VarDecl>("var");
41   SourceLocation Loc = Var->getLocation();
42   if (!Loc.isValid() || !utils::isPresumedLocInHeaderFile(Loc, *Result.SourceManager,
43                                                           HeaderFileExtensions))
44     return;
45   // If the initializer is a constant expression, then the compiler
46   // doesn't have to dynamically initialize it.
47   diag(Loc, "static variable %0 may be dynamically initialized in this header file")
48     << Var;
49 }
50 
51 } // namespace clang::tidy::bugprone
52