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/* -*- 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/.
*/
#include <cassert>
#include <string>
#include "clang/AST/Attr.h"
#include "clang/Sema/SemaInternal.h" // warn_unused_function
#include "compat.hxx"
#include "plugin.hxx"
namespace {
// It appears that, given a function declaration, there is no way to determine
// the language linkage of the function's type, only of the function's name
// (via FunctionDecl::isExternC); however, in a case like
//
// extern "C" { static void f(); }
//
// the function's name does not have C language linkage while the function's
// type does (as clarified in C++11 [decl.link]); cf. <http://clang-developers.
// 42468.n3.nabble.com/Language-linkage-of-function-type-tt4037248.html>
// "Language linkage of function type":
bool hasCLanguageLinkageType(FunctionDecl const * decl) {
assert(decl != nullptr);
if (decl->isExternC()) {
return true;
}
#if (__clang_major__ == 3 && __clang_minor__ >= 3) || __clang_major__ > 3
if (decl->isInExternCContext()) {
return true;
}
#else
if (decl->getCanonicalDecl()->getDeclContext()->isExternCContext()) {
return true;
}
#endif
return false;
}
class UnrefFun: public RecursiveASTVisitor<UnrefFun>, public loplugin::Plugin {
public:
explicit UnrefFun(InstantiationData const & data): Plugin(data) {}
void run() override
{ TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
bool VisitFunctionDecl(FunctionDecl const * decl);
};
bool UnrefFun::VisitFunctionDecl(FunctionDecl const * decl) {
if (ignoreLocation(decl)) {
return true;
}
//TODO, filtering out anything template for now:
if (decl->isDependentContext()) {
return true;
}
CXXRecordDecl const * r = dyn_cast<CXXRecordDecl>(decl->getDeclContext());;
if (r != nullptr && r->getTemplateSpecializationKind() != TSK_Undeclared) {
return true;
}
FunctionDecl const * canon = decl->getCanonicalDecl();
//TODO: is that the first?
if (canon->isDeleted() || canon->isReferenced()
|| !(canon->isDefined()
? decl->isThisDeclarationADefinition()
: compat::isFirstDecl(*decl))
|| !compat::isInMainFile(
compiler.getSourceManager(), canon->getLocation())
|| isInUnoIncludeFile(
compiler.getSourceManager().getSpellingLoc(
canon->getNameInfo().getLoc()))
|| canon->isMain()
|| (compiler.getDiagnostics().getDiagnosticLevel(
diag::warn_unused_function, decl->getLocation())
< DiagnosticsEngine::Warning))
{
return true;
}
compat::LinkageInfo info(canon->getLinkageAndVisibility());
if (compat::getLinkage(info) == ExternalLinkage
&& hasCLanguageLinkageType(canon) && canon->isDefined()
&& ((decl == canon && compat::getVisibility(info) == DefaultVisibility)
|| ((canon->hasAttr<ConstructorAttr>()
|| canon->hasAttr<DestructorAttr>())
&& compat::getVisibility(info) == HiddenVisibility)))
{
return true;
}
report(
DiagnosticsEngine::Warning,
(canon->isDefined()
#if (__clang_major__ == 3 && __clang_minor__ >= 4) || __clang_major__ > 3
? (canon->isExternallyVisible()
? "Unreferenced externally visible function definition"
: "Unreferenced externally invisible function definition")
#else
? "Unreferenced function definition"
#endif
: "Unreferenced function declaration"),
decl->getLocation())
<< decl->getSourceRange();
if (canon->isDefined() && !compat::isFirstDecl(*decl)) {
report(
DiagnosticsEngine::Note, "first declaration is here",
canon->getLocation())
<< canon->getSourceRange();
}
return true;
}
loplugin::Plugin::Registration<UnrefFun> X("unreffun");
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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