diff options
Diffstat (limited to 'compilerplugins/clang/defaultparams.cxx')
-rw-r--r-- | compilerplugins/clang/defaultparams.cxx | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/compilerplugins/clang/defaultparams.cxx b/compilerplugins/clang/defaultparams.cxx new file mode 100644 index 000000000000..173cc5e11604 --- /dev/null +++ b/compilerplugins/clang/defaultparams.cxx @@ -0,0 +1,80 @@ +/* -*- 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 <string> +#include <set> + +#include "plugin.hxx" + +// Find places where we call a method with values == the values specified in the parameter defaults. +// i.e. where the code might as well not specify anything. + +namespace { + +class DefaultParams: + public RecursiveASTVisitor<DefaultParams>, public loplugin::Plugin +{ +public: + explicit DefaultParams(InstantiationData const & data): Plugin(data) {} + + virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); } + + bool VisitCallExpr(const CallExpr * callExpr); +}; + +bool DefaultParams::VisitCallExpr(const CallExpr * callExpr) { + if (ignoreLocation(callExpr)) { + return true; + } + if (callExpr->getNumArgs() == 0) { + return true; + } + if (callExpr->getDirectCallee() == nullptr) { + return true; + } + const FunctionDecl* functionDecl = callExpr->getDirectCallee()->getCanonicalDecl(); + unsigned i = callExpr->getNumArgs() - 1; + const Expr* arg = callExpr->getArg(i); + // variadic functions + if (i >= functionDecl->getNumParams()) { + return true; + } + const ParmVarDecl* parmVarDecl = functionDecl->getParamDecl(i); + const Expr* defaultArgExpr = parmVarDecl->getDefaultArg(); + if (!arg->isDefaultArgument() && + arg->isIntegerConstantExpr(compiler.getASTContext()) && + parmVarDecl->hasDefaultArg() && + !parmVarDecl->hasUninstantiatedDefaultArg() && + defaultArgExpr->isIntegerConstantExpr(compiler.getASTContext())) + { + APSInt x1, x2; + if (arg->EvaluateAsInt(x1, compiler.getASTContext()) && + defaultArgExpr->EvaluateAsInt(x2, compiler.getASTContext()) && + x1 == x2) + { + report( + DiagnosticsEngine::Warning, + "not necessary to pass this argument, it defaults to the same value", + callExpr->getSourceRange().getBegin()) + << callExpr->getSourceRange(); + report( + DiagnosticsEngine::Warning, + "default method parameter declaration here", + parmVarDecl->getSourceRange().getBegin()) + << parmVarDecl->getSourceRange(); + } + } + return true; +} + +loplugin::Plugin::Registration< DefaultParams > X("defaultparams", false); + +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |