1 files changed, 118 insertions, 0 deletions
diff --git a/compilerplugins/clang/stringstatic.cxx b/compilerplugins/clang/stringstatic.cxx
new file mode 100644
index 0000000000..a7439608d5
--- /dev/null
+++ b/compilerplugins/clang/stringstatic.cxx
@@ -0,0 +1,118 @@
+/* -*- 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 "check.hxx"
+#include "plugin.hxx"
+
+/** Look for static O*String and O*String[] which can be constepxr.
+ */
+namespace {
+
+class StringStatic
+    : public loplugin::FilteringPlugin<StringStatic>
+{
+
+public:
+    explicit StringStatic(loplugin::InstantiationData const& rData):
+        FilteringPlugin(rData) {}
+
+    void run() override;
+    bool VisitVarDecl(VarDecl const*);
+};
+
+void StringStatic::run()
+{
+    if( preRun())
+        if( TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()))
+            postRun();
+}
+
+bool StringStatic::VisitVarDecl(VarDecl const* varDecl)
+{
+    if (ignoreLocation(varDecl))
+        return true;
+    QualType qt = varDecl->getType();
+    if (!varDecl->isThisDeclarationADefinition()
+        || !qt.isConstQualified() || varDecl->isConstexpr())
+        return true;
+
+    if (varDecl->hasGlobalStorage())
+    {
+        if (qt->isArrayType())
+            qt = qt->getAsArrayTypeUnsafe()->getElementType();
+
+        auto tc = loplugin::TypeCheck(qt);
+        if (!tc.Class("OUString").Namespace("rtl").GlobalNamespace()
+            && !tc.Class("OString").Namespace("rtl").GlobalNamespace())
+            return true;
+        if (varDecl->hasInit())
+        {
+            Expr const * expr = varDecl->getInit();
+            while (true) {
+                if (ExprWithCleanups const * exprWithCleanups = dyn_cast<ExprWithCleanups>(expr)) {
+                    expr = exprWithCleanups->getSubExpr();
+                }
+                else if (CastExpr const * castExpr = dyn_cast<CastExpr>(expr)) {
+                    expr = castExpr->getSubExpr();
+                }
+                else if (MaterializeTemporaryExpr const * materializeExpr = dyn_cast<MaterializeTemporaryExpr>(expr)) {
+                    expr = materializeExpr->getSubExpr();
+                }
+                else if (CXXBindTemporaryExpr const * bindExpr = dyn_cast<CXXBindTemporaryExpr>(expr)) {
+                    expr = bindExpr->getSubExpr();
+                }
+                else if (CXXConstructExpr const * constructExpr = dyn_cast<CXXConstructExpr>(expr)) {
+                    if (constructExpr->getNumArgs() == 0) {
+                        return true;
+                    }
+                    expr = constructExpr->getArg(0);
+                } else if (isa<CallExpr>(expr)) {
+                    return true;
+                } else {
+                    break;
+                }
+            }
+        }
+    }
+    else
+    {
+        if (isa<ParmVarDecl>(varDecl))
+            return true;
+        loplugin::TypeCheck const tc(varDecl->getType());
+        if (!(tc.Class("OString").Namespace("rtl").GlobalNamespace()
+              || tc.Class("OUString").Namespace("rtl").GlobalNamespace()))
+        {
+            return true;
+        }
+        if (varDecl->hasInit())
+        {
+            auto cxxConstruct = dyn_cast<CXXConstructExpr>(varDecl->getInit()->IgnoreImplicit());
+            if (!cxxConstruct || cxxConstruct->getNumArgs() == 0)
+                return true;
+            if (!isa<clang::StringLiteral>(cxxConstruct->getArg(0)))
+                return true;
+        }
+    }
+    report(DiagnosticsEngine::Warning,
+           "rather declare this as constexpr",
+           varDecl->getLocation())
+        << varDecl->getSourceRange();
+
+    return true;
+}
+
+loplugin::Plugin::Registration<StringStatic> stringstatic("stringstatic");
+
+} // namespace
+
+#endif // LO_CLANG_SHARED_PLUGINS
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */