1 files changed, 100 insertions, 0 deletions
diff --git a/compilerplugins/clang/staticaccess.cxx b/compilerplugins/clang/staticaccess.cxx
new file mode 100644
index 000000000..46aa033f0
--- /dev/null
+++ b/compilerplugins/clang/staticaccess.cxx
@@ -0,0 +1,100 @@
+/* -*- 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 <cassert>
+
+#include "plugin.hxx"
+
+namespace {
+
+bool isStatic(ValueDecl const * decl, bool * memberEnumerator) {
+    assert(memberEnumerator != nullptr);
+    // clang::MemberExpr::getMemberDecl is documented to return either a
+    // FieldDecl or a CXXMethodDecl, but can apparently also return a VarDecl
+    // (as C++ static data members are modeled by VarDecl, not FieldDecl) or an
+    // EnumConstantDecl (struct { enum {E}; } s; s.E;), see
+    // <https://reviews.llvm.org/D23907> "Fix documentation of
+    // MemberExpr::getMemberDecl":
+    auto fd = dyn_cast<FieldDecl>(decl);
+    if (fd != nullptr) {
+        *memberEnumerator = false;
+        return false;
+    }
+    auto vd = dyn_cast<VarDecl>(decl);
+    if (vd != nullptr) {
+        *memberEnumerator = false;
+        assert(vd->isStaticDataMember());
+        return true;
+    }
+    auto md = dyn_cast<CXXMethodDecl>(decl);
+    if (md != nullptr) {
+        *memberEnumerator = false;
+        return md->isStatic();
+    }
+    assert(dyn_cast<EnumConstantDecl>(decl) != nullptr);
+    *memberEnumerator = true;
+    return true;
+}
+
+class StaticAccess:
+    public loplugin::FilteringPlugin<StaticAccess>
+{
+public:
+    explicit StaticAccess(loplugin::InstantiationData const & data):
+        FilteringPlugin(data) {}
+
+    void run() override
+    { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
+
+    bool VisitMemberExpr(MemberExpr const * expr);
+};
+
+bool StaticAccess::VisitMemberExpr(MemberExpr const * expr) {
+    if (ignoreLocation(expr)) {
+        return true;
+    }
+    auto decl = expr->getMemberDecl();
+    bool me;
+    if (!isStatic(decl, &me)) {
+        return true;
+    }
+    auto const loc = expr->getExprLoc();
+    if (compiler.getSourceManager().isMacroBodyExpansion(loc)) {
+        auto const name = Lexer::getImmediateMacroName(
+            loc, compiler.getSourceManager(), compiler.getLangOpts());
+        if (name == "BEGIN_COM_MAP" || name == "DEFAULT_REFLECTION_HANDLER") {
+            // .../VC/Tools/MSVC/14.14.26428/atlmfc/include\atlcom.h(2226,10):  note: expanded from
+            //   macro 'BEGIN_COM_MAP'
+            //     return this->InternalQueryInterface(this, _GetEntries(), iid, ppvObject);
+            //            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
+            // .../VC/Tools/MSVC/14.14.26428/atlmfc/include\atlwin.h(2890,5):  note: expanded from
+            //   macro 'DEFAULT_REFLECTION_HANDLER'
+            //     if(this->DefaultReflectionHandler(hWnd, uMsg, wParam, lParam, lResult))
+            //        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+            return true;
+        }
+    }
+    report(
+        DiagnosticsEngine::Warning,
+        ("accessing %select{static class member|member enumerator}0 through"
+         " class member access syntax, use a qualified name like '%1' instead"),
+        expr->getBeginLoc())
+        << me << decl->getQualifiedNameAsString() << expr->getSourceRange();
+    return true;
+}
+
+loplugin::Plugin::Registration<StaticAccess> staticaccess("staticaccess");
+
+} // namespace
+
+#endif // LO_CLANG_SHARED_PLUGINS
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */