[clang-tools-extra] [clang-tidy] new check misc-use-internal-linkage (PR #90830)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,79 @@
+//===--- UseInternalLinkageCheck.cpp - clang-tidy--------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "UseInternalLinkageCheck.h"
+#include "clang/AST/Decl.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/ASTMatchers/ASTMatchersMacros.h"
+#include "clang/Basic/Specifiers.h"
+#include "llvm/ADT/STLExtras.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::misc {
+
+namespace {
+
+AST_POLYMORPHIC_MATCHER(isFirstDecl,
+                        AST_POLYMORPHIC_SUPPORTED_TYPES(FunctionDecl,
+                                                        VarDecl)) {
+  return Node.isFirstDecl();
+}
+
+AST_MATCHER(Decl, isInMainFile) {
+  return llvm::all_of(Node.redecls(), [&](const Decl *D) {
+    return Finder->getASTContext().getSourceManager().isInMainFile(
+        D->getLocation());
+  });
+}
+
+AST_POLYMORPHIC_MATCHER(isExternStorageClass,
+                        AST_POLYMORPHIC_SUPPORTED_TYPES(FunctionDecl,
+                                                        VarDecl)) {
+  return Node.getStorageClass() == SC_Extern;
+}
+
+} // namespace
+
+void UseInternalLinkageCheck::registerMatchers(MatchFinder *Finder) {
+  auto Common = allOf(isFirstDecl(), isInMainFile(),
+                      unless(anyOf(
+                          // 1. internal linkage
+                          isStaticStorageClass(), isInAnonymousNamespace(),
+                          // 2. explicit external linkage
+                          isExternStorageClass(), isExternC(),
+                          // 3. template
+                          isExplicitTemplateSpecialization(),
+                          clang::ast_matchers::isTemplateInstantiation(),
----------------
5chmidti wrote:

Template instantiations will already be ignored because of the traversal kind

https://github.com/llvm/llvm-project/pull/90830