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

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,78 @@
+//===--- 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 "../utils/FileExtensionsUtils.h"
+#include "clang/AST/Decl.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/ASTMatchers/ASTMatchersMacros.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/Specifiers.h"
+#include "llvm/ADT/STLExtras.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::misc {
+
+namespace {
+
+AST_MATCHER(Decl, isFirstDecl) { return Node.isFirstDecl(); }
+
+AST_MATCHER_P(Decl, isInMainFile, FileExtensionsSet, HeaderFileExtensions) {
+  return llvm::all_of(Node.redecls(), [&](const Decl *D) {
+    SourceManager &SM = Finder->getASTContext().getSourceManager();
+    const SourceLocation L = D->getLocation();
+    return SM.isInMainFile(L) &&
+           !utils::isSpellingLocInHeaderFile(L, SM, HeaderFileExtensions);
+  });
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PiotrZSL wrote:

yes, that FirstDecl stuff will work. just note that we got config for header extensions and source extensions. better would be to use source. as those .inc could be part of header files also.

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