[llvm] Replace LLVM_ATTRIBUTE_NORETURN with C++11 [[noreturn]]

[[noreturn]] can be used since Oct 2016 when the minimum compiler requirement was bumped to GCC 4.8/MSVC 2015.

Note: the definition of LLVM_ATTRIBUTE_NORETURN is kept for now.

33 files changed, 94 insertions, 119 deletions

diff --git a/llvm/include/llvm/MC/MCContext.h b/llvm/include/llvm/MC/MCContext.h
index 877b2dc..bde7507 100644
--- a/llvm/include/llvm/MC/MCContext.h
+++ b/llvm/include/llvm/MC/MCContext.h
@@ -817,7 +817,7 @@ namespace llvm {
     // Unrecoverable error has occurred. Display the best diagnostic we can
     // and bail via exit(1). For now, most MC backend errors are unrecoverable.
     // FIXME: We should really do something about that.
-    LLVM_ATTRIBUTE_NORETURN void reportFatalError(SMLoc L, const Twine &Msg);
+    [[noreturn]] void reportFatalError(SMLoc L, const Twine &Msg);
 
     const MCAsmMacro *lookupMacro(StringRef Name) {
       StringMap<MCAsmMacro>::iterator I = MacroMap.find(Name);
diff --git a/llvm/include/llvm/Support/CrashRecoveryContext.h b/llvm/include/llvm/Support/CrashRecoveryContext.h
index 4986906..2604ccb 100644
--- a/llvm/include/llvm/Support/CrashRecoveryContext.h
+++ b/llvm/include/llvm/Support/CrashRecoveryContext.h
@@ -99,8 +99,7 @@ public:
 
   /// Explicitly trigger a crash recovery in the current process, and
   /// return failure from RunSafely(). This function does not return.
-  LLVM_ATTRIBUTE_NORETURN
-  void HandleExit(int RetCode);
+  [[noreturn]] void HandleExit(int RetCode);
 
   /// Throw again a signal or an exception, after it was catched once by a
   /// CrashRecoveryContext.
diff --git a/llvm/include/llvm/Support/Error.h b/llvm/include/llvm/Support/Error.h
index e8f340e..4708d5b 100644
--- a/llvm/include/llvm/Support/Error.h
+++ b/llvm/include/llvm/Support/Error.h
@@ -257,8 +257,7 @@ private:
   // of debug prints can cause the function to be too large for inlining.  So
   // it's important that we define this function out of line so that it can't be
   // inlined.
-  LLVM_ATTRIBUTE_NORETURN
-  void fatalUncheckedError() const;
+  [[noreturn]] void fatalUncheckedError() const;
 #endif
 
   void assertIsChecked() {
@@ -688,9 +687,7 @@ private:
   }
 
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
-  LLVM_ATTRIBUTE_NORETURN
-  LLVM_ATTRIBUTE_NOINLINE
-  void fatalUncheckedExpected() const {
+  [[noreturn]] LLVM_ATTRIBUTE_NOINLINE void fatalUncheckedExpected() const {
     dbgs() << "Expected<T> must be checked before access or destruction.\n";
     if (HasError) {
       dbgs() << "Unchecked Expected<T> contained error:\n";
@@ -722,8 +719,7 @@ private:
 
 /// Report a serious error, calling any installed error handler. See
 /// ErrorHandling.h.
-LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err,
-                                                bool gen_crash_diag = true);
+[[noreturn]] void report_fatal_error(Error Err, bool gen_crash_diag = true);
 
 /// Report a fatal error if Err is a failure value.
 ///
diff --git a/llvm/include/llvm/Support/ErrorHandling.h b/llvm/include/llvm/Support/ErrorHandling.h
index 0ec0242..81cac47 100644
--- a/llvm/include/llvm/Support/ErrorHandling.h
+++ b/llvm/include/llvm/Support/ErrorHandling.h
@@ -68,14 +68,14 @@ class StringRef;
 /// standard error, followed by a newline.
 /// After the error handler is called this function will call abort(), it
 /// does not return.
-LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const char *reason,
-                                                bool gen_crash_diag = true);
-LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const std::string &reason,
-                                                bool gen_crash_diag = true);
-LLVM_ATTRIBUTE_NORETURN void report_fatal_error(StringRef reason,
-                                                bool gen_crash_diag = true);
-LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const Twine &reason,
-                                                bool gen_crash_diag = true);
+[[noreturn]] void report_fatal_error(const char *reason,
+                                     bool gen_crash_diag = true);
+[[noreturn]] void report_fatal_error(const std::string &reason,
+                                     bool gen_crash_diag = true);
+[[noreturn]] void report_fatal_error(StringRef reason,
+                                     bool gen_crash_diag = true);
+[[noreturn]] void report_fatal_error(const Twine &reason,
+                                     bool gen_crash_diag = true);
 
 /// Installs a new bad alloc error handler that should be used whenever a
 /// bad alloc error, e.g. failing malloc/calloc, is encountered by LLVM.
@@ -113,13 +113,13 @@ void install_out_of_memory_new_handler();
 /// If no error handler is installed (default), throws a bad_alloc exception
 /// if LLVM is compiled with exception support. Otherwise prints the error
 /// to standard error and calls abort().
-LLVM_ATTRIBUTE_NORETURN void report_bad_alloc_error(const char *Reason,
-                                                    bool GenCrashDiag = true);
+[[noreturn]] void report_bad_alloc_error(const char *Reason,
+                                         bool GenCrashDiag = true);
 
 /// This function calls abort(), and prints the optional message to stderr.
 /// Use the llvm_unreachable macro (that adds location info), instead of
 /// calling this function directly.
-LLVM_ATTRIBUTE_NORETURN void
+[[noreturn]] void
 llvm_unreachable_internal(const char *msg = nullptr, const char *file = nullptr,
                           unsigned line = 0);
 }
diff --git a/llvm/include/llvm/Support/Process.h b/llvm/include/llvm/Support/Process.h
index 6687e5e..ee03efe 100644
--- a/llvm/include/llvm/Support/Process.h
+++ b/llvm/include/llvm/Support/Process.h
@@ -214,12 +214,10 @@ public:
   /// In that case, the control flow will resume after RunSafely(), like for a
   /// crash, rather than exiting the current process.
   /// Use \arg NoCleanup for calling _exit() instead of exit().
-  LLVM_ATTRIBUTE_NORETURN
-  static void Exit(int RetCode, bool NoCleanup = false);
+  [[noreturn]] static void Exit(int RetCode, bool NoCleanup = false);
 
 private:
-  LLVM_ATTRIBUTE_NORETURN
-  static void ExitNoCleanup(int RetCode);
+  [[noreturn]] static void ExitNoCleanup(int RetCode);
 };
 
 }
diff --git a/llvm/include/llvm/Support/Windows/WindowsSupport.h b/llvm/include/llvm/Support/Windows/WindowsSupport.h
index a45eeab..e03d0da 100644
--- a/llvm/include/llvm/Support/Windows/WindowsSupport.h
+++ b/llvm/include/llvm/Support/Windows/WindowsSupport.h
@@ -68,7 +68,7 @@ llvm::VersionTuple GetWindowsOSVersion();
 bool MakeErrMsg(std::string *ErrMsg, const std::string &prefix);
 
 // Include GetLastError() in a fatal error message.
-LLVM_ATTRIBUTE_NORETURN inline void ReportLastErrorFatal(const char *Msg) {
+[[noreturn]] inline void ReportLastErrorFatal(const char *Msg) {
   std::string ErrMsg;
   MakeErrMsg(&ErrMsg, Msg);
   llvm::report_fatal_error(ErrMsg);
diff --git a/llvm/include/llvm/TableGen/Error.h b/llvm/include/llvm/TableGen/Error.h
index a0e23ac..da0132b 100644
--- a/llvm/include/llvm/TableGen/Error.h
+++ b/llvm/include/llvm/TableGen/Error.h
@@ -22,13 +22,10 @@ namespace llvm {
 void PrintNote(const Twine &Msg);
 void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg);
 
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(ArrayRef<SMLoc> ErrorLoc,
-                                            const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Record *Rec,
-                                            const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const RecordVal *RecVal,
-                                            const Twine &Msg);
+[[noreturn]] void PrintFatalNote(const Twine &Msg);
+[[noreturn]] void PrintFatalNote(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg);
+[[noreturn]] void PrintFatalNote(const Record *Rec, const Twine &Msg);
+[[noreturn]] void PrintFatalNote(const RecordVal *RecVal, const Twine &Msg);
 
 void PrintWarning(const Twine &Msg);
 void PrintWarning(ArrayRef<SMLoc> WarningLoc, const Twine &Msg);
@@ -40,13 +37,10 @@ void PrintError(const char *Loc, const Twine &Msg);
 void PrintError(const Record *Rec, const Twine &Msg);
 void PrintError(const RecordVal *RecVal, const Twine &Msg);
 
-LLVM_ATTRIBUTE_NORETURN void PrintFatalError(const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalError(ArrayRef<SMLoc> ErrorLoc,
-                                             const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalError(const Record *Rec,
-                                             const Twine &Msg);
-LLVM_ATTRIBUTE_NORETURN void PrintFatalError(const RecordVal *RecVal,
-                                             const Twine &Msg);
+[[noreturn]] void PrintFatalError(const Twine &Msg);
+[[noreturn]] void PrintFatalError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg);
+[[noreturn]] void PrintFatalError(const Record *Rec, const Twine &Msg);
+[[noreturn]] void PrintFatalError(const RecordVal *RecVal, const Twine &Msg);
 
 void CheckAssert(SMLoc Loc, Init *Condition, Init *Message);
 
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index 4e4ba4f..2840940 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -74,7 +74,7 @@ static cl::opt<bool> ThinLTOAssumeMerged(
     cl::desc("Assume the input has already undergone ThinLTO function "
              "importing and the other pre-optimization pipeline changes."));
 
-LLVM_ATTRIBUTE_NORETURN static void reportOpenError(StringRef Path, Twine Msg) {
+[[noreturn]] static void reportOpenError(StringRef Path, Twine Msg) {
   errs() << "failed to open " << Path << ": " << Msg << '\n';
   errs().flush();
   exit(1);
diff --git a/llvm/lib/Support/CrashRecoveryContext.cpp b/llvm/lib/Support/CrashRecoveryContext.cpp
index 433d99d..b6aaf37 100644
--- a/llvm/lib/Support/CrashRecoveryContext.cpp
+++ b/llvm/lib/Support/CrashRecoveryContext.cpp
@@ -428,8 +428,7 @@ bool CrashRecoveryContext::RunSafely(function_ref<void()> Fn) {
 
 #endif // !_MSC_VER
 
-LLVM_ATTRIBUTE_NORETURN
-void CrashRecoveryContext::HandleExit(int RetCode) {
+[[noreturn]] void CrashRecoveryContext::HandleExit(int RetCode) {
 #if defined(_WIN32)
   // SEH and VEH
   ::RaiseException(0xE0000000 | RetCode, 0, 0, NULL);
diff --git a/llvm/lib/Support/Process.cpp b/llvm/lib/Support/Process.cpp
index e7e9a8b..547b3b7 100644
--- a/llvm/lib/Support/Process.cpp
+++ b/llvm/lib/Support/Process.cpp
@@ -92,8 +92,7 @@ static bool coreFilesPrevented = !LLVM_ENABLE_CRASH_DUMPS;
 
 bool Process::AreCoreFilesPrevented() { return coreFilesPrevented; }
 
-LLVM_ATTRIBUTE_NORETURN
-void Process::Exit(int RetCode, bool NoCleanup) {
+[[noreturn]] void Process::Exit(int RetCode, bool NoCleanup) {
   if (CrashRecoveryContext *CRC = CrashRecoveryContext::GetCurrent())
     CRC->HandleExit(RetCode);
 
diff --git a/llvm/lib/Support/SmallVector.cpp b/llvm/lib/Support/SmallVector.cpp
index 0005f78..0e2378b 100644
--- a/llvm/lib/Support/SmallVector.cpp
+++ b/llvm/lib/Support/SmallVector.cpp
@@ -47,8 +47,7 @@ static_assert(sizeof(SmallVector<char, 0>) ==
 
 /// Report that MinSize doesn't fit into this vector's size type. Throws
 /// std::length_error or calls report_fatal_error.
-LLVM_ATTRIBUTE_NORETURN
-static void report_size_overflow(size_t MinSize, size_t MaxSize);
+[[noreturn]] static void report_size_overflow(size_t MinSize, size_t MaxSize);
 static void report_size_overflow(size_t MinSize, size_t MaxSize) {
   std::string Reason = "SmallVector unable to grow. Requested capacity (" +
                        std::to_string(MinSize) +
@@ -63,7 +62,7 @@ static void report_size_overflow(size_t MinSize, size_t MaxSize) {
 
 /// Report that this vector is already at maximum capacity. Throws
 /// std::length_error or calls report_fatal_error.
-LLVM_ATTRIBUTE_NORETURN static void report_at_maximum_capacity(size_t MaxSize);
+[[noreturn]] static void report_at_maximum_capacity(size_t MaxSize);
 static void report_at_maximum_capacity(size_t MaxSize) {
   std::string Reason =
       "SmallVector capacity unable to grow. Already at maximum size " +
diff --git a/llvm/lib/Support/Unix/Process.inc b/llvm/lib/Support/Unix/Process.inc
index 30b957e..d3d9fb7 100644
--- a/llvm/lib/Support/Unix/Process.inc
+++ b/llvm/lib/Support/Unix/Process.inc
@@ -461,5 +461,4 @@ unsigned llvm::sys::Process::GetRandomNumber() {
 #endif
 }
 
-LLVM_ATTRIBUTE_NORETURN
-void Process::ExitNoCleanup(int RetCode) { _Exit(RetCode); }
+[[noreturn]] void Process::ExitNoCleanup(int RetCode) { _Exit(RetCode); }
diff --git a/llvm/lib/Support/Unix/Unix.h b/llvm/lib/Support/Unix/Unix.h
index 6092913..e392434 100644
--- a/llvm/lib/Support/Unix/Unix.h
+++ b/llvm/lib/Support/Unix/Unix.h
@@ -67,8 +67,7 @@ static inline bool MakeErrMsg(
 }
 
 // Include StrError(errnum) in a fatal error message.
-LLVM_ATTRIBUTE_NORETURN static inline void ReportErrnumFatal(const char *Msg,
-                                                             int errnum) {
+[[noreturn]] static inline void ReportErrnumFatal(const char *Msg, int errnum) {
   std::string ErrMsg;
   MakeErrMsg(&ErrMsg, Msg, errnum);
   llvm::report_fatal_error(ErrMsg);
diff --git a/llvm/lib/Support/Windows/Process.inc b/llvm/lib/Support/Windows/Process.inc
index 6f58c52..a0d94e6 100644
--- a/llvm/lib/Support/Windows/Process.inc
+++ b/llvm/lib/Support/Windows/Process.inc
@@ -504,8 +504,7 @@ bool llvm::RunningWindows8OrGreater() {
   return GetWindowsOSVersion() >= llvm::VersionTuple(6, 2, 0, 0);
 }
 
-LLVM_ATTRIBUTE_NORETURN
-void Process::ExitNoCleanup(int RetCode) {
+[[noreturn]] void Process::ExitNoCleanup(int RetCode) {
   TerminateProcess(GetCurrentProcess(), RetCode);
   llvm_unreachable("TerminateProcess doesn't return");
 }
diff --git a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCodeEmitter.cpp b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCodeEmitter.cpp
index 24169c8..4779fa4 100644
--- a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCodeEmitter.cpp
+++ b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCodeEmitter.cpp
@@ -448,8 +448,7 @@ void HexagonMCCodeEmitter::EncodeSingleInstruction(const MCInst &MI,
   ++MCNumEmitted;
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void raise_relocation_error(unsigned Width, unsigned Kind) {
+[[noreturn]] static void raise_relocation_error(unsigned Width, unsigned Kind) {
   std::string Text;
   raw_string_ostream Stream(Text);
   Stream << "Unrecognized relocation combination: width=" << Width
diff --git a/llvm/lib/Transforms/Coroutines/Coroutines.cpp b/llvm/lib/Transforms/Coroutines/Coroutines.cpp
index ae2d9e1..c131e29 100644
--- a/llvm/lib/Transforms/Coroutines/Coroutines.cpp
+++ b/llvm/lib/Transforms/Coroutines/Coroutines.cpp
@@ -571,8 +571,8 @@ void coro::Shape::emitDealloc(IRBuilder<> &Builder, Value *Ptr,
   llvm_unreachable("Unknown coro::ABI enum");
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void fail(const Instruction *I, const char *Reason, Value *V) {
+[[noreturn]] static void fail(const Instruction *I, const char *Reason,
+                              Value *V) {
 #ifndef NDEBUG
   I->dump();
   if (V) {
diff --git a/llvm/tools/llc/llc.cpp b/llvm/tools/llc/llc.cpp
index 6a1e2ba..58f19b2 100644
--- a/llvm/tools/llc/llc.cpp
+++ b/llvm/tools/llc/llc.cpp
@@ -201,8 +201,7 @@ static cl::opt<RunPassOption, true, cl::parser<std::string>> RunPass(
 
 static int compileModule(char **, LLVMContext &);
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(Twine Msg,
-                                                StringRef Filename = "") {
+[[noreturn]] static void reportError(Twine Msg, StringRef Filename = "") {
   SmallString<256> Prefix;
   if (!Filename.empty()) {
     if (Filename == "-")
@@ -213,7 +212,7 @@ LLVM_ATTRIBUTE_NORETURN static void reportError(Twine Msg,
   exit(1);
 }
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(Error Err, StringRef Filename) {
+[[noreturn]] static void reportError(Error Err, StringRef Filename) {
   assert(Err);
   handleAllErrors(createFileError(Filename, std::move(Err)),
                   [&](const ErrorInfoBase &EI) { reportError(EI.message()); });
diff --git a/llvm/tools/lli/lli.cpp b/llvm/tools/lli/lli.cpp
index af614c0..170cc3b 100644
--- a/llvm/tools/lli/lli.cpp
+++ b/llvm/tools/lli/lli.cpp
@@ -410,8 +410,7 @@ CodeGenOpt::Level getOptLevel() {
   llvm_unreachable("Unrecognized opt level.");
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void reportError(SMDiagnostic Err, const char *ProgName) {
+[[noreturn]] static void reportError(SMDiagnostic Err, const char *ProgName) {
   Err.print(ProgName, errs());
   exit(1);
 }
diff --git a/llvm/tools/llvm-ar/llvm-ar.cpp b/llvm/tools/llvm-ar/llvm-ar.cpp
index 0e1dce6..68084ba 100644
--- a/llvm/tools/llvm-ar/llvm-ar.cpp
+++ b/llvm/tools/llvm-ar/llvm-ar.cpp
@@ -136,14 +136,14 @@ static unsigned MRILineNumber;
 static bool ParsingMRIScript;
 
 // Show the error plus the usage message, and exit.
-LLVM_ATTRIBUTE_NORETURN static void badUsage(Twine Error) {
+[[noreturn]] static void badUsage(Twine Error) {
   WithColor::error(errs(), ToolName) << Error << "\n";
   printHelpMessage();
   exit(1);
 }
 
 // Show the error message and exit.
-LLVM_ATTRIBUTE_NORETURN static void fail(Twine Error) {
+[[noreturn]] static void fail(Twine Error) {
   if (ParsingMRIScript) {
     WithColor::error(errs(), ToolName)
         << "script line " << MRILineNumber << ": " << Error << "\n";
diff --git a/llvm/tools/llvm-cvtres/llvm-cvtres.cpp b/llvm/tools/llvm-cvtres/llvm-cvtres.cpp
index 24b3c65..0907c0a 100644
--- a/llvm/tools/llvm-cvtres/llvm-cvtres.cpp
+++ b/llvm/tools/llvm-cvtres/llvm-cvtres.cpp
@@ -67,7 +67,7 @@ public:
 };
 }
 
-static LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
+[[noreturn]] static void reportError(Twine Msg) {
   errs() << Msg;
   exit(1);
 }
diff --git a/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp b/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
index f214288..4e1cca7 100644
--- a/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
+++ b/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
@@ -49,7 +49,7 @@ static void error(std::error_code EC) {
   exit(1);
 }
 
-LLVM_ATTRIBUTE_NORETURN static void error(Error Err) {
+[[noreturn]] static void error(Error Err) {
   logAllUnhandledErrors(std::move(Err), WithColor::error(outs()),
                         "reading file: ");
   outs().flush();
diff --git a/llvm/tools/llvm-ifs/ErrorCollector.cpp b/llvm/tools/llvm-ifs/ErrorCollector.cpp
index 087a30c..04daa84 100644
--- a/llvm/tools/llvm-ifs/ErrorCollector.cpp
+++ b/llvm/tools/llvm-ifs/ErrorCollector.cpp
@@ -57,7 +57,7 @@ ErrorCollector::~ErrorCollector() {
   }
 }
 
-LLVM_ATTRIBUTE_NORETURN void ErrorCollector::fatalUnhandledError() {
+[[noreturn]] void ErrorCollector::fatalUnhandledError() {
   errs() << "Program aborted due to unhandled Error(s):\n";
   log(errs());
   errs() << "\n";
diff --git a/llvm/tools/llvm-ifs/ErrorCollector.h b/llvm/tools/llvm-ifs/ErrorCollector.h
index 67996f4..7217ca3 100644
--- a/llvm/tools/llvm-ifs/ErrorCollector.h
+++ b/llvm/tools/llvm-ifs/ErrorCollector.h
@@ -61,7 +61,7 @@ private:
   bool allErrorsHandled() const;
 
   /// Dump output and crash.
-  LLVM_ATTRIBUTE_NORETURN void fatalUnhandledError();
+  [[noreturn]] void fatalUnhandledError();
 
   bool ErrorsAreFatal;
   std::vector<Error> Errors;
diff --git a/llvm/tools/llvm-lipo/llvm-lipo.cpp b/llvm/tools/llvm-lipo/llvm-lipo.cpp
index d099ea1..738f16a 100644
--- a/llvm/tools/llvm-lipo/llvm-lipo.cpp
+++ b/llvm/tools/llvm-lipo/llvm-lipo.cpp
@@ -36,13 +36,13 @@ using namespace llvm::object;
 static const StringRef ToolName = "llvm-lipo";
 static LLVMContext LLVMCtx;
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(Twine Message) {
+[[noreturn]] static void reportError(Twine Message) {
   WithColor::error(errs(), ToolName) << Message << "\n";
   errs().flush();
   exit(EXIT_FAILURE);
 }
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(Error E) {
+[[noreturn]] static void reportError(Error E) {
   assert(E);
   std::string Buf;
   raw_string_ostream OS(Buf);
@@ -51,7 +51,7 @@ LLVM_ATTRIBUTE_NORETURN static void reportError(Error E) {
   reportError(Buf);
 }
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(StringRef File, Error E) {
+[[noreturn]] static void reportError(StringRef File, Error E) {
   assert(E);
   std::string Buf;
   raw_string_ostream OS(Buf);
@@ -350,9 +350,9 @@ readInputBinaries(ArrayRef<InputFile> InputFiles) {
   return InputBinaries;
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void verifyArch(ArrayRef<OwningBinary<Binary>> InputBinaries,
-                       ArrayRef<std::string> VerifyArchList) {
+[[noreturn]] static void
+verifyArch(ArrayRef<OwningBinary<Binary>> InputBinaries,
+           ArrayRef<std::string> VerifyArchList) {
   assert(!VerifyArchList.empty() &&
          "The list of architectures should be non-empty");
   assert(InputBinaries.size() == 1 && "Incorrect number of input binaries");
@@ -433,15 +433,15 @@ static void printBinaryArchs(const Binary *Binary, raw_ostream &OS) {
   OS << SliceOrErr->getArchString() << " \n";
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void printArchs(ArrayRef<OwningBinary<Binary>> InputBinaries) {
+[[noreturn]] static void
+printArchs(ArrayRef<OwningBinary<Binary>> InputBinaries) {
   assert(InputBinaries.size() == 1 && "Incorrect number of input binaries");
   printBinaryArchs(InputBinaries.front().getBinary(), outs());
   exit(EXIT_SUCCESS);
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void printInfo(ArrayRef<OwningBinary<Binary>> InputBinaries) {
+[[noreturn]] static void
+printInfo(ArrayRef<OwningBinary<Binary>> InputBinaries) {
   // Group universal and thin files together for compatibility with cctools lipo
   for (auto &IB : InputBinaries) {
     const Binary *Binary = IB.getBinary();
@@ -463,9 +463,9 @@ static void printInfo(ArrayRef<OwningBinary<Binary>> InputBinaries) {
   exit(EXIT_SUCCESS);
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void thinSlice(ArrayRef<OwningBinary<Binary>> InputBinaries,
-                      StringRef ArchType, StringRef OutputFileName) {
+[[noreturn]] static void thinSlice(ArrayRef<OwningBinary<Binary>> InputBinaries,
+                                   StringRef ArchType,
+                                   StringRef OutputFileName) {
   assert(!ArchType.empty() && "The architecture type should be non-empty");
   assert(InputBinaries.size() == 1 && "Incorrect number of input binaries");
   assert(!OutputFileName.empty() && "Thin expects a single output file");
@@ -599,10 +599,10 @@ buildSlices(ArrayRef<OwningBinary<Binary>> InputBinaries,
   return Slices;
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void createUniversalBinary(ArrayRef<OwningBinary<Binary>> InputBinaries,
-                                  const StringMap<const uint32_t> &Alignments,
-                                  StringRef OutputFileName) {
+[[noreturn]] static void
+createUniversalBinary(ArrayRef<OwningBinary<Binary>> InputBinaries,
+                      const StringMap<const uint32_t> &Alignments,
+                      StringRef OutputFileName) {
   assert(InputBinaries.size() >= 1 && "Incorrect number of input binaries");
   assert(!OutputFileName.empty() && "Create expects a single output file");
 
@@ -619,10 +619,10 @@ static void createUniversalBinary(ArrayRef<OwningBinary<Binary>> InputBinaries,
   exit(EXIT_SUCCESS);
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void extractSlice(ArrayRef<OwningBinary<Binary>> InputBinaries,
-                         const StringMap<const uint32_t> &Alignments,
-                         StringRef ArchType, StringRef OutputFileName) {
+[[noreturn]] static void
+extractSlice(ArrayRef<OwningBinary<Binary>> InputBinaries,
+             const StringMap<const uint32_t> &Alignments, StringRef ArchType,
+             StringRef OutputFileName) {
   assert(!ArchType.empty() &&
          "The architecture type should be non-empty");
   assert(InputBinaries.size() == 1 && "Incorrect number of input binaries");
@@ -678,11 +678,10 @@ buildReplacementSlices(ArrayRef<OwningBinary<Binary>> ReplacementBinaries,
   return Slices;
 }
 
-LLVM_ATTRIBUTE_NORETURN
-static void replaceSlices(ArrayRef<OwningBinary<Binary>> InputBinaries,
-                          const StringMap<const uint32_t> &Alignments,
-                          StringRef OutputFileName,
-                          ArrayRef<InputFile> ReplacementFiles) {
+[[noreturn]] static void
+replaceSlices(ArrayRef<OwningBinary<Binary>> InputBinaries,
+              const StringMap<const uint32_t> &Alignments,
+              StringRef OutputFileName, ArrayRef<InputFile> ReplacementFiles) {
   assert(InputBinaries.size() == 1 && "Incorrect number of input binaries");
   assert(!OutputFileName.empty() && "Replace expects a single output file");
 
diff --git a/llvm/tools/llvm-mt/llvm-mt.cpp b/llvm/tools/llvm-mt/llvm-mt.cpp
index 6f26765..1ff66ee 100644
--- a/llvm/tools/llvm-mt/llvm-mt.cpp
+++ b/llvm/tools/llvm-mt/llvm-mt.cpp
@@ -64,7 +64,7 @@ public:
 };
 } // namespace
 
-LLVM_ATTRIBUTE_NORETURN static void reportError(Twine Msg) {
+[[noreturn]] static void reportError(Twine Msg) {
   WithColor::error(errs(), "llvm-mt") << Msg << '\n';
   exit(1);
 }
diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index 48ae92f..0e4f402 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -297,16 +297,15 @@ void objdump::reportWarning(const Twine &Message, StringRef File) {
       << "'" << File << "': " << Message << "\n";
 }
 
-LLVM_ATTRIBUTE_NORETURN void objdump::reportError(StringRef File,
-                                                  const Twine &Message) {
+[[noreturn]] void objdump::reportError(StringRef File, const Twine &Message) {
   outs().flush();
   WithColor::error(errs(), ToolName) << "'" << File << "': " << Message << "\n";
   exit(1);
 }
 
-LLVM_ATTRIBUTE_NORETURN void objdump::reportError(Error E, StringRef FileName,
-                                                  StringRef ArchiveName,
-                                                  StringRef ArchitectureName) {
+[[noreturn]] void objdump::reportError(Error E, StringRef FileName,
+                                       StringRef ArchiveName,
+                                       StringRef ArchitectureName) {
   assert(E);
   outs().flush();
   WithColor::error(errs(), ToolName);
@@ -325,7 +324,7 @@ static void reportCmdLineWarning(const Twine &Message) {
   WithColor::warning(errs(), ToolName) << Message << "\n";
 }
 
-LLVM_ATTRIBUTE_NORETURN static void reportCmdLineError(const Twine &Message) {
+[[noreturn]] static void reportCmdLineError(const Twine &Message) {
   WithColor::error(errs(), ToolName) << Message << "\n";
   exit(1);
 }
diff --git a/llvm/tools/llvm-objdump/llvm-objdump.h b/llvm/tools/llvm-objdump/llvm-objdump.h
index 33fb3f2..3796878 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.h
+++ b/llvm/tools/llvm-objdump/llvm-objdump.h
@@ -139,10 +139,10 @@ void printSymbolTable(const object::ObjectFile *O, StringRef ArchiveName,
 void printSymbol(const object::ObjectFile *O, const object::SymbolRef &Symbol,
                  StringRef FileName, StringRef ArchiveName,
                  StringRef ArchitectureName, bool DumpDynamic);
-LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, const Twine &Message);
-LLVM_ATTRIBUTE_NORETURN void reportError(Error E, StringRef FileName,
-                                         StringRef ArchiveName = "",
-                                         StringRef ArchitectureName = "");
+[[noreturn]] void reportError(StringRef File, const Twine &Message);
+[[noreturn]] void reportError(Error E, StringRef FileName,
+                              StringRef ArchiveName = "",
+                              StringRef ArchitectureName = "");
 void reportWarning(const Twine &Message, StringRef File);
 
 template <typename T, typename... Ts>
diff --git a/llvm/tools/llvm-profgen/ErrorHandling.h b/llvm/tools/llvm-profgen/ErrorHandling.h
index 1d118c5..5d08c01 100644
--- a/llvm/tools/llvm-profgen/ErrorHandling.h
+++ b/llvm/tools/llvm-profgen/ErrorHandling.h
@@ -18,9 +18,9 @@
 
 using namespace llvm;
 
-LLVM_ATTRIBUTE_NORETURN inline void
-exitWithError(const Twine &Message, StringRef Whence = StringRef(),
-              StringRef Hint = StringRef()) {
+[[noreturn]] inline void exitWithError(const Twine &Message,
+                                       StringRef Whence = StringRef(),
+                                       StringRef Hint = StringRef()) {
   WithColor::error(errs(), "llvm-profgen");
   if (!Whence.empty())
     errs() << Whence.str() << ": ";
@@ -30,12 +30,12 @@ exitWithError(const Twine &Message, StringRef Whence = StringRef(),
   ::exit(EXIT_FAILURE);
 }
 
-LLVM_ATTRIBUTE_NORETURN inline void
-exitWithError(std::error_code EC, StringRef Whence = StringRef()) {
+[[noreturn]] inline void exitWithError(std::error_code EC,
+                                       StringRef Whence = StringRef()) {
   exitWithError(EC.message(), Whence);
 }
 
-LLVM_ATTRIBUTE_NORETURN inline void exitWithError(Error E, StringRef Whence) {
+[[noreturn]] inline void exitWithError(Error E, StringRef Whence) {
   exitWithError(errorToErrorCode(std::move(E)), Whence);
 }
 
diff --git a/llvm/tools/llvm-rc/llvm-rc.cpp b/llvm/tools/llvm-rc/llvm-rc.cpp
index 0f70e30..c7c93ae 100644
--- a/llvm/tools/llvm-rc/llvm-rc.cpp
+++ b/llvm/tools/llvm-rc/llvm-rc.cpp
@@ -111,7 +111,7 @@ static ExitOnError ExitOnErr;
 static FileRemover TempPreprocFile;
 static FileRemover TempResFile;
 
-LLVM_ATTRIBUTE_NORETURN static void fatalError(const Twine &Message) {
+[[noreturn]] static void fatalError(const Twine &Message) {
   errs() << Message << "\n";
   exit(1);
 }
diff --git a/llvm/tools/llvm-readobj/llvm-readobj.cpp b/llvm/tools/llvm-readobj/llvm-readobj.cpp
index 0b49f03..76ac5be 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.cpp
+++ b/llvm/tools/llvm-readobj/llvm-readobj.cpp
@@ -157,7 +157,7 @@ static StringRef ToolName;
 
 namespace llvm {
 
-LLVM_ATTRIBUTE_NORETURN static void error(Twine Msg) {
+[[noreturn]] static void error(Twine Msg) {
   // Flush the standard output to print the error at a
   // proper place.
   fouts().flush();
@@ -165,7 +165,7 @@ LLVM_ATTRIBUTE_NORETURN static void error(Twine Msg) {
   exit(1);
 }
 
-LLVM_ATTRIBUTE_NORETURN void reportError(Error Err, StringRef Input) {
+[[noreturn]] void reportError(Error Err, StringRef Input) {
   assert(Err);
   if (Input == "-")
     Input = "<stdin>";
diff --git a/llvm/tools/llvm-readobj/llvm-readobj.h b/llvm/tools/llvm-readobj/llvm-readobj.h
index 43d19b4..7672da5 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.h
+++ b/llvm/tools/llvm-readobj/llvm-readobj.h
@@ -21,7 +21,7 @@ namespace llvm {
   }
 
   // Various helper functions.
-  LLVM_ATTRIBUTE_NORETURN void reportError(Error Err, StringRef Input); 
+  [[noreturn]] void reportError(Error Err, StringRef Input);
   void reportWarning(Error Err, StringRef Input);
 
   template <class T> T unwrapOrError(StringRef Input, Expected<T> EO) {
diff --git a/llvm/tools/llvm-strings/llvm-strings.cpp b/llvm/tools/llvm-strings/llvm-strings.cpp
index 0b068749..e7c50f8 100644
--- a/llvm/tools/llvm-strings/llvm-strings.cpp
+++ b/llvm/tools/llvm-strings/llvm-strings.cpp
@@ -73,7 +73,7 @@ static bool PrintFileName;
 enum radix { none, octal, hexadecimal, decimal };
 static radix Radix;
 
-LLVM_ATTRIBUTE_NORETURN static void reportCmdLineError(const Twine &Message) {
+[[noreturn]] static void reportCmdLineError(const Twine &Message) {
   WithColor::error(errs(), ToolName) << Message << "\n";
   exit(1);
 }
diff --git a/llvm/tools/split-file/split-file.cpp b/llvm/tools/split-file/split-file.cpp
index 3ebbda4..3556784 100644
--- a/llvm/tools/split-file/split-file.cpp
+++ b/llvm/tools/split-file/split-file.cpp
@@ -42,8 +42,7 @@ static cl::opt<bool> noLeadingLines("no-leading-lines",
 static StringRef toolName;
 static int errorCount;
 
-LLVM_ATTRIBUTE_NORETURN static void fatal(StringRef filename,
-                                          const Twine &message) {
+[[noreturn]] static void fatal(StringRef filename, const Twine &message) {
   if (filename.empty())
     WithColor::error(errs(), toolName) << message << '\n';
   else