[[maybe_unused]], proper CMake flag setup

jansvoboda11 · jansvoboda11 · commit 692e38c1b4ac · 2025-10-06T14:32:55.000-07:00
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1414,7 +1414,7 @@ void clang::emitBackendOutput(CompilerInstance &CI, CodeGenOptions &CGOpts,
   std::unique_ptr<llvm::Module> EmptyModule;
   if (!CGOpts.ThinLTOIndexFile.empty()) {
     // FIXME(sandboxing): Figure out how to support distributed indexing.
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     // If we are performing a ThinLTO importing compile, load the function index
     // into memory and pass it into runThinLTOBackend, which will run the
     // function importer and invoke LTO passes.
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
@@ -1872,7 +1872,7 @@ bool Driver::getCrashDiagnosticFile(StringRef ReproCrashFilename,
   assert(llvm::Triple(llvm::sys::getProcessTriple()).isOSDarwin() &&
          "Only knows about .crash files on Darwin");
   // This is not a formal output of the compiler, let's bypass the sandbox.
-  auto BypassSandbox = sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sandbox::scopedDisable();
 
   // The .crash file can be found on at ~/Library/Logs/DiagnosticReports/
   // (or /Library/Logs/DiagnosticReports for root) and has the filename pattern
diff --git a/clang/lib/Driver/Job.cpp b/clang/lib/Driver/Job.cpp
@@ -428,7 +428,7 @@ int CC1Command::Execute(ArrayRef<std::optional<StringRef>> Redirects,
 
   // Enabling the sandbox here allows us to restore its previous state even when
   // this cc1 invocation crashes.
-  auto EnableSandbox = llvm::sys::sandbox::scopedEnable();
+  [[maybe_unused]] auto EnableSandbox = llvm::sys::sandbox::scopedEnable();
 
   llvm::CrashRecoveryContext CRC;
   CRC.DumpStackAndCleanupOnFailure = true;
diff --git a/clang/lib/Serialization/GlobalModuleIndex.cpp b/clang/lib/Serialization/GlobalModuleIndex.cpp
@@ -252,7 +252,7 @@ GlobalModuleIndex::~GlobalModuleIndex() {
 std::pair<GlobalModuleIndex *, llvm::Error>
 GlobalModuleIndex::readIndex(StringRef Path) {
   // This is a compiler-internal input/output, let's bypass the sandbox.
-  auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
 
   // Load the index file, if it's there.
   llvm::SmallString<128> IndexPath;
@@ -848,7 +848,7 @@ GlobalModuleIndex::writeIndex(FileManager &FileMgr,
                               const PCHContainerReader &PCHContainerRdr,
                               StringRef Path) {
   // This is a compiler-internal input/output, let's bypass the sandbox.
-  auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
 
   llvm::SmallString<128> IndexPath;
   IndexPath += Path;
diff --git a/clang/lib/Serialization/ModuleCache.cpp b/clang/lib/Serialization/ModuleCache.cpp
@@ -29,7 +29,7 @@ void clang::maybePruneImpl(StringRef Path, time_t PruneInterval,
     return;
 
   // This is a compiler-internal input/output, let's bypass the sandbox.
-  auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
 
   llvm::SmallString<128> TimestampFile(Path);
   llvm::sys::path::append(TimestampFile, "modules.timestamp");
@@ -120,7 +120,7 @@ class CrossProcessModuleCache : public ModuleCache {
 
   std::time_t getModuleTimestamp(StringRef ModuleFilename) override {
     // This is a compiler-internal input/output, let's bypass the sandbox.
-    auto SandboxBypass = llvm::sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
     llvm::sys::fs::file_status Status;
     if (llvm::sys::fs::status(ModuleFilename, Status) != std::error_code{})
       return 0;
diff --git a/clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp b/clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
@@ -259,7 +259,7 @@ void HTMLDiagnostics::FlushDiagnosticsImpl(
 void HTMLDiagnostics::ReportDiag(const PathDiagnostic& D,
                                  FilesMade *filesMade) {
   // FIXME(sandboxing): Remove this by adopting `llvm::vfs::OutputBackend`.
-  auto SandboxBypass = llvm::sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
 
   // Create the HTML directory if it is missing.
   if (!createdDir) {
diff --git a/clang/tools/driver/cc1_main.cpp b/clang/tools/driver/cc1_main.cpp
@@ -274,7 +274,7 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
 
   /// Create the actual file system.
   auto VFS = [] {
-    auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
     return llvm::vfs::getRealFileSystem();
   }();
   Clang->createVirtualFileSystem(std::move(VFS), DiagsBuffer);
@@ -309,7 +309,7 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   // results now.  This happens in -disable-free mode.
   {
     // This isn't a formal input or output of the compiler.
-    auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = llvm::sys::sandbox::scopedDisable();
     std::unique_ptr<raw_ostream> IOFile = llvm::CreateInfoOutputFile();
     if (Clang->getCodeGenOpts().TimePassesJson) {
       *IOFile << "{\n";
diff --git a/clang/tools/driver/cc1as_main.cpp b/clang/tools/driver/cc1as_main.cpp
@@ -427,7 +427,7 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
 
   ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer = [=] {
     // FIXME(sandboxing): Make this a proper input file.
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     return MemoryBuffer::getFileOrSTDIN(Opts.InputFile, /*IsText=*/true);
   }();
 
@@ -674,7 +674,7 @@ int cc1as_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   DiagnosticsEngine Diags(DiagnosticIDs::create(), DiagOpts, DiagClient);
 
   auto VFS = [] {
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     return vfs::getRealFileSystem();
   }();
 
diff --git a/llvm/include/llvm/Config/llvm-config.h.cmake b/llvm/include/llvm/Config/llvm-config.h.cmake
@@ -126,6 +126,9 @@
  * in non assert builds */
 #cmakedefine01 LLVM_UNREACHABLE_OPTIMIZE
 
+/* Define if building LLVM with LLVM_ENABLE_IO_SANDBOX */
+#cmakedefine01 LLVM_ENABLE_IO_SANDBOX
+
 /* Define to 1 if you have the DIA SDK installed, and to 0 if you don't. */
 #cmakedefine01 LLVM_ENABLE_DIA_SDK
 
diff --git a/llvm/include/llvm/Support/IOSandbox.h b/llvm/include/llvm/Support/IOSandbox.h
@@ -29,8 +29,8 @@ inline void violationIfEnabled() {
 #else
 
 namespace llvm::sys::sandbox {
-inline int scopedEnable() {}
-inline int scopedDisable() {}
+inline int scopedEnable() { return 0; }
+inline int scopedDisable() { return 0; }
 inline void violationIfEnabled() {}
 } // namespace llvm::sys::sandbox
 
diff --git a/llvm/lib/Support/LockFileManager.cpp b/llvm/lib/Support/LockFileManager.cpp
@@ -52,7 +52,7 @@ using namespace llvm;
 /// \returns The process ID of the process that owns this lock file
 std::optional<LockFileManager::OwnedByAnother>
 LockFileManager::readLockFile(StringRef LockFileName) {
-  auto SandboxBypass = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
 
   // Read the owning host and PID out of the lock file. If it appears that the
   // owning process is dead, the lock file is invalid.
@@ -249,7 +249,7 @@ Expected<bool> LockFileManager::tryLock() {
 }
 
 LockFileManager::~LockFileManager() {
-  auto SandboxBypass = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
 
   if (!std::holds_alternative<OwnedByUs>(Owner))
     return;
diff --git a/llvm/lib/Support/Signals.cpp b/llvm/lib/Support/Signals.cpp
@@ -97,7 +97,7 @@ CallBacksToRun() {
 // Signal-safe.
 void sys::RunSignalHandlers() {
   // Let's not interfere with stack trace symbolication and friends.
-  auto BypassSandbox = sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sandbox::scopedDisable();
 
   for (CallbackAndCookie &RunMe : CallBacksToRun()) {
     auto Expected = CallbackAndCookie::Status::Initialized;
diff --git a/llvm/lib/Support/VirtualFileSystem.cpp b/llvm/lib/Support/VirtualFileSystem.cpp
@@ -222,7 +222,7 @@ RealFile::~RealFile() { close(); }
 ErrorOr<Status> RealFile::status() {
   assert(FD != kInvalidFile && "cannot stat closed file");
   if (!S.isStatusKnown()) {
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     file_status RealStatus;
     if (std::error_code EC = sys::fs::status(FD, RealStatus))
       return EC;
@@ -239,7 +239,7 @@ ErrorOr<std::unique_ptr<MemoryBuffer>>
 RealFile::getBuffer(const Twine &Name, int64_t FileSize,
                     bool RequiresNullTerminator, bool IsVolatile) {
   assert(FD != kInvalidFile && "cannot get buffer for closed file");
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
   return MemoryBuffer::getOpenFile(FD, Name, FileSize, RequiresNullTerminator,
                                    IsVolatile);
 }
@@ -309,7 +309,7 @@ class RealFileSystem : public FileSystem {
 
   ErrorOr<std::unique_ptr<File>>
   openFileForReadWithFlags(const Twine &Name, sys::fs::OpenFlags Flags) {
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     SmallString<256> RealName, Storage;
     Expected<file_t> FDOrErr = sys::fs::openNativeFileForRead(
         adjustPath(Name, Storage), Flags, &RealName);
@@ -331,7 +331,7 @@ class RealFileSystem : public FileSystem {
 } // namespace
 
 ErrorOr<Status> RealFileSystem::status(const Twine &Path) {
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
   SmallString<256> Storage;
   sys::fs::file_status RealStatus;
   if (std::error_code EC =
@@ -356,7 +356,7 @@ llvm::ErrorOr<std::string> RealFileSystem::getCurrentWorkingDirectory() const {
   if (WD)
     return WD->getError();
 
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
   SmallString<128> Dir;
   if (std::error_code EC = llvm::sys::fs::current_path(Dir))
     return EC;
@@ -387,7 +387,7 @@ std::error_code RealFileSystem::isLocal(const Twine &Path, bool &Result) {
 
 std::error_code RealFileSystem::getRealPath(const Twine &Path,
                                             SmallVectorImpl<char> &Output) {
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
   SmallString<256> Storage;
   return llvm::sys::fs::real_path(adjustPath(Path, Storage), Output);
 }
@@ -422,14 +422,14 @@ class RealFSDirIter : public llvm::vfs::detail::DirIterImpl {
 
 public:
   RealFSDirIter(const Twine &Path, std::error_code &EC) {
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     Iter = llvm::sys::fs::directory_iterator{Path, EC};
     if (Iter != llvm::sys::fs::directory_iterator())
       CurrentEntry = directory_entry(Iter->path(), Iter->type());
   }
 
   std::error_code increment() override {
-    auto BypassSandbox = sys::sandbox::scopedDisable();
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
     std::error_code EC;
     Iter.increment(EC);
     CurrentEntry = (Iter == llvm::sys::fs::directory_iterator())
diff --git a/llvm/lib/Support/VirtualOutputBackends.cpp b/llvm/lib/Support/VirtualOutputBackends.cpp
@@ -554,7 +554,7 @@ Error OnDiskOutputFile::keep() {
 }
 
 Error OnDiskOutputFile::discard() {
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
 
   // Destroy the streams to flush them.
   if (auto E = reset())
@@ -585,7 +585,7 @@ Error OnDiskOutputBackend::makeAbsolute(SmallVectorImpl<char> &Path) const {
 Expected<std::unique_ptr<OutputFileImpl>>
 OnDiskOutputBackend::createFileImpl(StringRef Path,
                                     std::optional<OutputConfig> Config) {
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
 
   SmallString<256> AbsPath;
   if (Path != "-") {
diff --git a/llvm/lib/Support/raw_ostream.cpp b/llvm/lib/Support/raw_ostream.cpp
@@ -619,7 +619,7 @@ raw_fd_ostream::raw_fd_ostream(int fd, bool shouldClose, bool unbuffered,
                                OStreamKind K)
     : raw_pwrite_stream(unbuffered, K), FD(fd), ShouldClose(shouldClose) {
   // FIXME(sandboxing): Remove this by adopting `llvm::vfs::OutputBackend`.
-  auto BypassSandbox = sys::sandbox::scopedDisable();
+  [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
 
   if (FD < 0 ) {
     ShouldClose = false;
