1 files changed, 89 insertions, 0 deletions
diff --git a/compilerplugins/clang/data.cxx b/compilerplugins/clang/data.cxx
new file mode 100644
index 000000000..9cff5426f
--- /dev/null
+++ b/compilerplugins/clang/data.cxx
@@ -0,0 +1,89 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * 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 "compat.hxx"
+#include "plugin.hxx"
+
+// For std::array or std::vector x, replace &x[0] with x.data().
+
+namespace
+{
+class Data final : public loplugin::FilteringPlugin<Data>
+{
+public:
+    explicit Data(loplugin::InstantiationData const& data)
+        : FilteringPlugin(data)
+    {
+    }
+
+    bool VisitUnaryOperator(UnaryOperator const* expr)
+    {
+        if (ignoreLocation(expr))
+        {
+            return true;
+        }
+        if (expr->getOpcode() != UO_AddrOf)
+        {
+            return true;
+        }
+        auto const e1 = dyn_cast<CXXOperatorCallExpr>(expr->getSubExpr()->IgnoreParenImpCasts());
+        if (e1 == nullptr)
+        {
+            return true;
+        }
+        if (e1->getOperator() != OO_Subscript)
+        {
+            return true;
+        }
+        auto const t = e1->getArg(0)->getType();
+        auto const chk = loplugin::TypeCheck(t);
+        if (!(chk.Class("array").StdNamespace() || chk.Class("vector").StdNamespace()))
+        {
+            return true;
+        }
+        auto const e2 = e1->getArg(1);
+        if (e2->isValueDependent())
+        {
+            return true;
+        }
+        APSInt v;
+        if (!compat::EvaluateAsInt(e2, v, compiler.getASTContext()))
+        {
+            return true;
+        }
+        if (v != 0)
+        {
+            return true;
+        }
+        report(DiagnosticsEngine::Warning,
+               "use 'data' member function to access first element of %0", expr->getExprLoc())
+            << t << expr->getSourceRange();
+        return true;
+    }
+
+    bool preRun() override { return compiler.getLangOpts().CPlusPlus; }
+
+    void run() override
+    {
+        if (preRun())
+        {
+            TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+        }
+    }
+};
+
+static loplugin::Plugin::Registration<Data> data("data");
+
+} // namespace
+
+#endif // LO_CLANG_SHARED_PLUGINS
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */