[clang-tools-extra] [clang-tools-extra] Replace LLVM_ATTRIBUTE_UNUSED with [[maybe_unused]] (NFC) (PR #163915)

Thu Oct 16 23:41:41 PDT 2025

llvmbot wrote:



@llvm/pr-subscribers-clangd

@llvm/pr-subscribers-clang-tools-extra

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>

This patch replaces LLVM_ATTRIBUTE_UNUSED with [[maybe_unused]],
introduced as part of C++17.


---
Full diff: https://github.com/llvm/llvm-project/pull/163915.diff


6 Files Affected:

- (modified) clang-tools-extra/clang-doc/Generators.cpp (+5-9) 
- (modified) clang-tools-extra/clang-tidy/ClangTidyForceLinker.h (+25-26) 
- (modified) clang-tools-extra/clangd/FindTarget.cpp (+1-1) 
- (modified) clang-tools-extra/clangd/unittests/FileDistanceTests.cpp (+1-1) 
- (modified) clang-tools-extra/clangd/unittests/QualityTests.cpp (+1-1) 
- (modified) clang-tools-extra/clangd/unittests/URITests.cpp (+1-1) 


``````````diff

diff --git a/clang-tools-extra/clang-doc/Generators.cpp b/clang-tools-extra/clang-doc/Generators.cpp
index 3fb5b63c403a7..a5f6f1c7ea732 100644
--- a/clang-tools-extra/clang-doc/Generators.cpp
+++ b/clang-tools-extra/clang-doc/Generators.cpp
@@ -97,15 +97,11 @@ void Generator::addInfoToIndex(Index &Idx, const doc::Info *Info) {
 
 // This anchor is used to force the linker to link in the generated object file
 // and thus register the generators.
-static int LLVM_ATTRIBUTE_UNUSED YAMLGeneratorAnchorDest =
-    YAMLGeneratorAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED MDGeneratorAnchorDest =
-    MDGeneratorAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED HTMLGeneratorAnchorDest =
-    HTMLGeneratorAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED MHTMLGeneratorAnchorDest =
+[[maybe_unused]] static int YAMLGeneratorAnchorDest = YAMLGeneratorAnchorSource;
+[[maybe_unused]] static int MDGeneratorAnchorDest = MDGeneratorAnchorSource;
+[[maybe_unused]] static int HTMLGeneratorAnchorDest = HTMLGeneratorAnchorSource;
+[[maybe_unused]] static int MHTMLGeneratorAnchorDest =
     MHTMLGeneratorAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED JSONGeneratorAnchorDest =
-    JSONGeneratorAnchorSource;
+[[maybe_unused]] static int JSONGeneratorAnchorDest = JSONGeneratorAnchorSource;
 } // namespace doc
 } // namespace clang
diff --git a/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h b/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
index cdf6ce2045a5d..afc358ad4e966 100644
--- a/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
+++ b/clang-tools-extra/clang-tidy/ClangTidyForceLinker.h
@@ -16,132 +16,131 @@ namespace clang::tidy {
 
 // This anchor is used to force the linker to link the AbseilModule.
 extern volatile int AbseilModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED AbseilModuleAnchorDestination =
+[[maybe_unused]] static int AbseilModuleAnchorDestination =
     AbseilModuleAnchorSource;
 
 // This anchor is used to force the linker to link the AlteraModule.
 extern volatile int AlteraModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED AlteraModuleAnchorDestination =
+[[maybe_unused]] static int AlteraModuleAnchorDestination =
     AlteraModuleAnchorSource;
 
 // This anchor is used to force the linker to link the AndroidModule.
 extern volatile int AndroidModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED AndroidModuleAnchorDestination =
+[[maybe_unused]] static int AndroidModuleAnchorDestination =
     AndroidModuleAnchorSource;
 
 // This anchor is used to force the linker to link the BoostModule.
 extern volatile int BoostModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED BoostModuleAnchorDestination =
+[[maybe_unused]] static int BoostModuleAnchorDestination =
     BoostModuleAnchorSource;
 
 // This anchor is used to force the linker to link the BugproneModule.
 extern volatile int BugproneModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED BugproneModuleAnchorDestination =
+[[maybe_unused]] static int BugproneModuleAnchorDestination =
     BugproneModuleAnchorSource;
 
 // This anchor is used to force the linker to link the CERTModule.
 extern volatile int CERTModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED CERTModuleAnchorDestination =
+[[maybe_unused]] static int CERTModuleAnchorDestination =
     CERTModuleAnchorSource;
 
 // This anchor is used to force the linker to link the ConcurrencyModule.
 extern volatile int ConcurrencyModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED ConcurrencyModuleAnchorDestination =
+[[maybe_unused]] static int ConcurrencyModuleAnchorDestination =
     ConcurrencyModuleAnchorSource;
 
 // This anchor is used to force the linker to link the CppCoreGuidelinesModule.
 extern volatile int CppCoreGuidelinesModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED CppCoreGuidelinesModuleAnchorDestination =
+[[maybe_unused]] static int CppCoreGuidelinesModuleAnchorDestination =
     CppCoreGuidelinesModuleAnchorSource;
 
 #if CLANG_TIDY_ENABLE_QUERY_BASED_CUSTOM_CHECKS
 // This anchor is used to force the linker to link the CustomModule.
 extern volatile int CustomModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED CustomModuleAnchorDestination =
+[[maybe_unused]] static int CustomModuleAnchorDestination =
     CustomModuleAnchorSource;
 #endif
 
 // This anchor is used to force the linker to link the DarwinModule.
 extern volatile int DarwinModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED DarwinModuleAnchorDestination =
+[[maybe_unused]] static int DarwinModuleAnchorDestination =
     DarwinModuleAnchorSource;
 
 // This anchor is used to force the linker to link the FuchsiaModule.
 extern volatile int FuchsiaModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED FuchsiaModuleAnchorDestination =
+[[maybe_unused]] static int FuchsiaModuleAnchorDestination =
     FuchsiaModuleAnchorSource;
 
 // This anchor is used to force the linker to link the GoogleModule.
 extern volatile int GoogleModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED GoogleModuleAnchorDestination =
+[[maybe_unused]] static int GoogleModuleAnchorDestination =
     GoogleModuleAnchorSource;
 
 // This anchor is used to force the linker to link the HICPPModule.
 extern volatile int HICPPModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED HICPPModuleAnchorDestination =
+[[maybe_unused]] static int HICPPModuleAnchorDestination =
     HICPPModuleAnchorSource;
 
 // This anchor is used to force the linker to link the LinuxKernelModule.
 extern volatile int LinuxKernelModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED LinuxKernelModuleAnchorDestination =
+[[maybe_unused]] static int LinuxKernelModuleAnchorDestination =
     LinuxKernelModuleAnchorSource;
 
 // This anchor is used to force the linker to link the LLVMModule.
 extern volatile int LLVMModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED LLVMModuleAnchorDestination =
+[[maybe_unused]] static int LLVMModuleAnchorDestination =
     LLVMModuleAnchorSource;
 
 // This anchor is used to force the linker to link the LLVMLibcModule.
 extern volatile int LLVMLibcModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED LLVMLibcModuleAnchorDestination =
+[[maybe_unused]] static int LLVMLibcModuleAnchorDestination =
     LLVMLibcModuleAnchorSource;
 
 // This anchor is used to force the linker to link the MiscModule.
 extern volatile int MiscModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED MiscModuleAnchorDestination =
+[[maybe_unused]] static int MiscModuleAnchorDestination =
     MiscModuleAnchorSource;
 
 // This anchor is used to force the linker to link the ModernizeModule.
 extern volatile int ModernizeModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED ModernizeModuleAnchorDestination =
+[[maybe_unused]] static int ModernizeModuleAnchorDestination =
     ModernizeModuleAnchorSource;
 
 #if CLANG_TIDY_ENABLE_STATIC_ANALYZER &&                                       \
     !defined(CLANG_TIDY_DISABLE_STATIC_ANALYZER_CHECKS)
 // This anchor is used to force the linker to link the MPIModule.
 extern volatile int MPIModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED MPIModuleAnchorDestination =
-    MPIModuleAnchorSource;
+[[maybe_unused]] static int MPIModuleAnchorDestination = MPIModuleAnchorSource;
 #endif
 
 // This anchor is used to force the linker to link the ObjCModule.
 extern volatile int ObjCModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED ObjCModuleAnchorDestination =
+[[maybe_unused]] static int ObjCModuleAnchorDestination =
     ObjCModuleAnchorSource;
 
 // This anchor is used to force the linker to link the OpenMPModule.
 extern volatile int OpenMPModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED OpenMPModuleAnchorDestination =
+[[maybe_unused]] static int OpenMPModuleAnchorDestination =
     OpenMPModuleAnchorSource;
 
 // This anchor is used to force the linker to link the PerformanceModule.
 extern volatile int PerformanceModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED PerformanceModuleAnchorDestination =
+[[maybe_unused]] static int PerformanceModuleAnchorDestination =
     PerformanceModuleAnchorSource;
 
 // This anchor is used to force the linker to link the PortabilityModule.
 extern volatile int PortabilityModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED PortabilityModuleAnchorDestination =
+[[maybe_unused]] static int PortabilityModuleAnchorDestination =
     PortabilityModuleAnchorSource;
 
 // This anchor is used to force the linker to link the ReadabilityModule.
 extern volatile int ReadabilityModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED ReadabilityModuleAnchorDestination =
+[[maybe_unused]] static int ReadabilityModuleAnchorDestination =
     ReadabilityModuleAnchorSource;
 
 // This anchor is used to force the linker to link the ZirconModule.
 extern volatile int ZirconModuleAnchorSource;
-static int LLVM_ATTRIBUTE_UNUSED ZirconModuleAnchorDestination =
+[[maybe_unused]] static int ZirconModuleAnchorDestination =
     ZirconModuleAnchorSource;
 
 } // namespace clang::tidy
diff --git a/clang-tools-extra/clangd/FindTarget.cpp b/clang-tools-extra/clangd/FindTarget.cpp
index ce79f88e18446..f80f7325d17ae 100644
--- a/clang-tools-extra/clangd/FindTarget.cpp
+++ b/clang-tools-extra/clangd/FindTarget.cpp
@@ -50,7 +50,7 @@ namespace clang {
 namespace clangd {
 namespace {
 
-LLVM_ATTRIBUTE_UNUSED std::string nodeToString(const DynTypedNode &N) {
+[[maybe_unused]] std::string nodeToString(const DynTypedNode &N) {
   std::string S = std::string(N.getNodeKind().asStringRef());
   {
     llvm::raw_string_ostream OS(S);
diff --git a/clang-tools-extra/clangd/unittests/FileDistanceTests.cpp b/clang-tools-extra/clangd/unittests/FileDistanceTests.cpp
index 3003582959af3..aed3400ab1296 100644
--- a/clang-tools-extra/clangd/unittests/FileDistanceTests.cpp
+++ b/clang-tools-extra/clangd/unittests/FileDistanceTests.cpp
@@ -58,7 +58,7 @@ TEST(FileDistanceTests, BadSource) {
 }
 
 // Force the unittest URI scheme to be linked,
-static int LLVM_ATTRIBUTE_UNUSED UseUnittestScheme = UnittestSchemeAnchorSource;
+[[maybe_unused]] static int UseUnittestScheme = UnittestSchemeAnchorSource;
 
 TEST(FileDistanceTests, URI) {
   FileDistanceOptions Opts;
diff --git a/clang-tools-extra/clangd/unittests/QualityTests.cpp b/clang-tools-extra/clangd/unittests/QualityTests.cpp
index 4954659a45e02..879a1793128c0 100644
--- a/clang-tools-extra/clangd/unittests/QualityTests.cpp
+++ b/clang-tools-extra/clangd/unittests/QualityTests.cpp
@@ -33,7 +33,7 @@ namespace clang {
 namespace clangd {
 
 // Force the unittest URI scheme to be linked,
-static int LLVM_ATTRIBUTE_UNUSED UnittestSchemeAnchorDest =
+[[maybe_unused]] static int UnittestSchemeAnchorDest =
     UnittestSchemeAnchorSource;
 
 namespace {
diff --git a/clang-tools-extra/clangd/unittests/URITests.cpp b/clang-tools-extra/clangd/unittests/URITests.cpp
index 99d59b65cbbc1..c0ccfc539c452 100644
--- a/clang-tools-extra/clangd/unittests/URITests.cpp
+++ b/clang-tools-extra/clangd/unittests/URITests.cpp
@@ -16,7 +16,7 @@ namespace clang {
 namespace clangd {
 
 // Force the unittest URI scheme to be linked,
-static int LLVM_ATTRIBUTE_UNUSED UnittestSchemeAnchorDest =
+[[maybe_unused]] static int UnittestSchemeAnchorDest =
     UnittestSchemeAnchorSource;
 
 namespace {

``````````

</details>


https://github.com/llvm/llvm-project/pull/163915
