diff options
Diffstat (limited to 'compilerplugins/clang/overrideparam.cxx')
| -rw-r--r-- | compilerplugins/clang/overrideparam.cxx | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/compilerplugins/clang/overrideparam.cxx b/compilerplugins/clang/overrideparam.cxx new file mode 100644 index 000000000..61efe15b1 --- /dev/null +++ b/compilerplugins/clang/overrideparam.cxx @@ -0,0 +1,166 @@ +/* -*- 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/. + */ +#ifndef LO_CLANG_SHARED_PLUGINS + +#include <string> +#include <set> + +#include "plugin.hxx" +#include "check.hxx" + +/* + Find overridden methods that : + (a) declare default params in different places to their super-method(s) + + Still TODO + (b) Find places where the values of the default parameters are different + (c) Find places where the names of the parameters differ +*/ + +namespace { + +class OverrideParam: + public loplugin::FilteringPlugin<OverrideParam> +{ +public: + explicit OverrideParam(loplugin::InstantiationData const & data): + FilteringPlugin(data) {} + + virtual void run() override; + + bool VisitCXXMethodDecl(const CXXMethodDecl *); + +private: + bool hasSameDefaultParams(const ParmVarDecl * parmVarDecl, const ParmVarDecl * superParmVarDecl); +}; + +void OverrideParam::run() +{ + if (preRun()) + TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); +} + +bool OverrideParam::VisitCXXMethodDecl(const CXXMethodDecl * methodDecl) { + if (ignoreLocation(methodDecl)) { + return true; + } + if (methodDecl->isThisDeclarationADefinition() || methodDecl->size_overridden_methods() == 0) { + return true; + } + loplugin::DeclCheck dc(methodDecl); + // This class is overriding ShowCursor(bool) AND declaring a ShowCursor() method. + // Adding a default param causes 'ambiguous override'. + if (dc.Function("ShowCursor").Class("ScTabViewShell").GlobalNamespace()) { + return true; + } + + for(auto superMethodIt = methodDecl->begin_overridden_methods(); + superMethodIt != methodDecl->end_overridden_methods(); ++superMethodIt) + { + const CXXMethodDecl * superMethodDecl = *superMethodIt; + if (ignoreLocation(superMethodDecl)) { + continue; + } + int i = 0; + for (const ParmVarDecl *superParmVarDecl : superMethodDecl->parameters()) { + const ParmVarDecl *parmVarDecl = methodDecl->getParamDecl(i); + if (parmVarDecl->hasDefaultArg() && !superParmVarDecl->hasDefaultArg()) { + report( + DiagnosticsEngine::Warning, + "overridden method declaration has default arg, but super-method does not", + parmVarDecl->getSourceRange().getBegin()) + << parmVarDecl->getSourceRange(); + report( + DiagnosticsEngine::Note, + "original param here", + superParmVarDecl->getSourceRange().getBegin()) + << superParmVarDecl->getSourceRange(); + } + else if (!parmVarDecl->hasDefaultArg() && superParmVarDecl->hasDefaultArg()) { + report( + DiagnosticsEngine::Warning, + "overridden method declaration has no default arg, but super-method does", + parmVarDecl->getSourceRange().getBegin()) + << parmVarDecl->getSourceRange(); + report( + DiagnosticsEngine::Note, + "original param here", + superParmVarDecl->getSourceRange().getBegin()) + << superParmVarDecl->getSourceRange(); + } + else if (parmVarDecl->hasDefaultArg() && superParmVarDecl->hasDefaultArg() + && !hasSameDefaultParams(parmVarDecl, superParmVarDecl)) { + report( + DiagnosticsEngine::Warning, + "overridden method declaration has different default param to super-method", + parmVarDecl->getSourceRange().getBegin()) + << parmVarDecl->getSourceRange(); + report( + DiagnosticsEngine::Note, + "original param here", + superParmVarDecl->getSourceRange().getBegin()) + << superParmVarDecl->getSourceRange(); + } + /* do nothing for now, will enable this in a later commit + if (methodDecl->isThisDeclarationADefinition() && parmVarDecl->getName().empty()) { + // ignore this - means the param is unused + } + else if (superParmVarDecl->getName().empty()) { + // ignore, nothing reasonable I can do + } + else if (superParmVarDecl->getName() != parmVarDecl->getName()) { + report( + DiagnosticsEngine::Warning, + "overridden method declaration uses different name for parameter", + parmVarDecl->getSourceRange().getBegin()) + << parmVarDecl->getSourceRange(); + report( + DiagnosticsEngine::Note, + "original param here", + superParmVarDecl->getSourceRange().getBegin()) + << superParmVarDecl->getSourceRange(); + }*/ + ++i; + } + } + return true; +} + +bool OverrideParam::hasSameDefaultParams(const ParmVarDecl * parmVarDecl, const ParmVarDecl * superParmVarDecl) +{ + // don't know what this means, but it prevents a clang crash + if (parmVarDecl->hasUninstantiatedDefaultArg() || superParmVarDecl->hasUninstantiatedDefaultArg()) { + return true; + } + return + checkIdenticalDefaultArguments( + parmVarDecl->getDefaultArg(), superParmVarDecl->getDefaultArg()) + != IdenticalDefaultArgumentsResult::No; + // for one, Clang 3.8 doesn't have EvaluateAsFloat; for another, since + // <http://llvm.org/viewvc/llvm-project?view=revision&revision=291318> + // "PR23135: Don't instantiate constexpr functions referenced in + // unevaluated operands where possible", default args are not + // necessarily evaluated, so the above calls to EvaluateAsInt etc. may + // fail (as they do e.g. for SfxViewShell::SetPrinter and derived + // classes' 'SfxPrinterChangeFlags nDiffFlags = SFX_PRINTER_ALL' arg, + // include/sfx2/viewsh.hxx; what appears would help is to call + // 'compiler.getSema().MarkDeclarationsReferencedInExpr()' on + // defaultArgExpr and superDefaultArgExpr before any of the calls to + // EvaluateAsInt etc., cf. the implementation of + // Sema::CheckCXXDefaultArgExpr in Clang's lib/Sema/SemaExpr.cpp, but + // that would probably have unwanted side-effects) +} + +loplugin::Plugin::Registration< OverrideParam > overrideparam("overrideparam"); + +} // namespace + +#endif // LO_CLANG_SHARED_PLUGINS + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |