diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index 461b723bd736b..6b80d4291c0ee 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -222,7 +222,7 @@ jobs:
           python3 -m venv .venv
           source .venv/bin/activate
           python -m pip install psutil
-          bash libcxx/utils/ci/run-buildbot ${{ matrix.config }}
+          xcrun bash libcxx/utils/ci/run-buildbot ${{ matrix.config }}
       - uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
         if: always()  # Upload artifacts even if the build or test suite fails
         with:
diff --git a/clang/lib/Driver/ToolChains/Gnu.cpp b/clang/lib/Driver/ToolChains/Gnu.cpp
index 07df986463690..b7cd5f6be14a6 100644
--- a/clang/lib/Driver/ToolChains/Gnu.cpp
+++ b/clang/lib/Driver/ToolChains/Gnu.cpp
@@ -1796,11 +1796,11 @@ static void findRISCVBareMetalMultilibs(const Driver &D,
   std::string MArch = tools::riscv::getRISCVArch(Args, TargetTriple);
   for (auto Element : RISCVMultilibSet) {
     addMultilibFlag(MArch == Element.march,
-                    Twine("-march=", Element.march).str().c_str(), Flags);
+                    Twine("-march=", Element.march).str(), Flags);
     if (!Added_ABIs.count(Element.mabi)) {
       Added_ABIs.insert(Element.mabi);
       addMultilibFlag(ABIName == Element.mabi,
-                      Twine("-mabi=", Element.mabi).str().c_str(), Flags);
+                      Twine("-mabi=", Element.mabi).str(), Flags);
     }
   }
 
diff --git a/libcxx/utils/ci/run-buildbot b/libcxx/utils/ci/run-buildbot
index 57ecf1e49dbf2..d265dddebe11f 100755
--- a/libcxx/utils/ci/run-buildbot
+++ b/libcxx/utils/ci/run-buildbot
@@ -35,8 +35,6 @@ CC                  The C compiler to use, this value is used by CMake. This
 CXX                 The C++ compiler to use, this value is used by CMake. This
                     variable is optional.
 
-CMAKE               The CMake binary to use. This variable is optional.
-
 CLANG_FORMAT        The clang-format binary to use when generating the format
                     ignore list.
 
@@ -73,29 +71,6 @@ MONOREPO_ROOT="${MONOREPO_ROOT:="$(git rev-parse --show-toplevel)"}"
 BUILD_DIR="${BUILD_DIR:=${MONOREPO_ROOT}/build/${BUILDER}}"
 INSTALL_DIR="${BUILD_DIR}/install"
 
-# If we can find Ninja/CMake provided by Xcode, use those since we know their
-# version will generally work with the Clang shipped in Xcode (e.g. if Clang
-# knows about -std=c++20, the CMake bundled in Xcode will probably know about
-# that flag too).
-if xcrun --find ninja &>/dev/null; then
-    NINJA="$(xcrun --find ninja)"
-elif which ninja &>/dev/null; then
-    # The current implementation of modules needs the absolute path to the ninja
-    # binary.
-    # TODO MODULES Is this still needed when CMake has libc++ module support?
-    NINJA="$(which ninja)"
-else
-    NINJA="ninja"
-fi
-
-if [ -z "${CMAKE}" ]; then
-    if xcrun --find cmake &>/dev/null; then
-        CMAKE="$(xcrun --find cmake)"
-    else
-        CMAKE="cmake"
-    fi
-fi
-
 function step() {
   endstep
   set +x
@@ -129,10 +104,10 @@ function generate-cmake-base() {
     step "Generating CMake"
 
     # We can remove -DCMAKE_INSTALL_MESSAGE=NEVER once https://gitlab.kitware.com/cmake/cmake/-/issues/26085 is fixed.
-    ${CMAKE} \
+    cmake \
           -S "${MONOREPO_ROOT}/runtimes" \
           -B "${BUILD_DIR}" \
-          -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+          -GNinja \
           -DCMAKE_BUILD_TYPE=RelWithDebInfo \
           -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
           -DLIBCXX_ENABLE_WERROR=YES \
@@ -168,25 +143,25 @@ function generate-cmake-android() {
 
 function check-runtimes() {
     step "Building libc++ test dependencies"
-    ${NINJA} -vC "${BUILD_DIR}" cxx-test-depends
+    ninja -vC "${BUILD_DIR}" cxx-test-depends
 
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 
     step "Running the libc++abi tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxxabi
+    ninja -vC "${BUILD_DIR}" check-cxxabi
 
     step "Running the libunwind tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-unwind
+    ninja -vC "${BUILD_DIR}" check-unwind
 }
 
 # TODO: The goal is to test this against all configurations. We should also move
 #       this to the Lit test suite instead of being a separate CMake target.
 function check-abi-list() {
     step "Running the libc++ ABI list test"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx-abilist || (
+    ninja -vC "${BUILD_DIR}" check-cxx-abilist || (
         error "Generating the libc++ ABI list after failed check"
-        ${NINJA} -vC "${BUILD_DIR}" generate-cxx-abilist
+        ninja -vC "${BUILD_DIR}" generate-cxx-abilist
         false
     )
 }
@@ -212,10 +187,10 @@ function test-armv7m-picolibc() {
     # architecture name, which is not what Clang's driver expects to find.
     # The install location will however be wrong with
     # LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON, so we correct that below.
-    ${CMAKE} \
+    cmake \
         -S "${MONOREPO_ROOT}/compiler-rt" \
         -B "${BUILD_DIR}/compiler-rt" \
-        -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+        -GNinja \
         -DCMAKE_BUILD_TYPE=RelWithDebInfo \
         -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
         -DCMAKE_C_FLAGS="${flags}" \
@@ -233,7 +208,7 @@ function test-armv7m-picolibc() {
         "${@}"
 
     step "Installing compiler-rt"
-    ${NINJA} -vC "${BUILD_DIR}/compiler-rt" install
+    ninja -vC "${BUILD_DIR}/compiler-rt" install
     # Move compiler-rt libs into the same directory as all the picolib objects.
     mv "${INSTALL_DIR}/lib/armv7m-unknown-none-eabi"/* "${INSTALL_DIR}/lib"
 
@@ -242,8 +217,8 @@ function test-armv7m-picolibc() {
 
 # Print the version of a few tools to aid diagnostics in some cases
 step "Diagnose tools in use"
-${CMAKE} --version
-${NINJA} --version
+cmake --version
+ninja --version
 if [ ! -z "${CXX}" ]; then ${CXX} --version; fi
 
 case "${BUILDER}" in
@@ -256,7 +231,7 @@ check-generated-output)
     # Reject patches that forgot to re-run the generator scripts.
     step "Making sure the generator scripts were run"
     set +x # Printing all the commands below just creates extremely confusing output
-    ${NINJA} -vC "${BUILD_DIR}" libcxx-generate-files
+    ninja -vC "${BUILD_DIR}" libcxx-generate-files
     git diff | tee ${BUILD_DIR}/generated_output.patch
     git ls-files -o --exclude-standard | tee ${BUILD_DIR}/generated_output.status
     ! grep -q '^--- a' ${BUILD_DIR}/generated_output.patch || false
@@ -383,10 +358,10 @@ bootstrapping-build)
     clean
 
     step "Generating CMake"
-    ${CMAKE} \
+    cmake \
           -S "${MONOREPO_ROOT}/llvm" \
           -B "${BUILD_DIR}" \
-          -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+          -GNinja \
           -DCMAKE_CXX_COMPILER_LAUNCHER="ccache" \
           -DCMAKE_BUILD_TYPE=Release \
           -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}" \
@@ -400,13 +375,13 @@ bootstrapping-build)
           -DLLVM_LIT_ARGS="-sv --xunit-xml-output test-results.xml --timeout=1500 --time-tests"
 
     step "Running the libc++ and libc++abi tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-runtimes
+    ninja -vC "${BUILD_DIR}" check-runtimes
 
     step "Installing libc++ and libc++abi to a fake location"
-    ${NINJA} -vC "${BUILD_DIR}" install-runtimes
+    ninja -vC "${BUILD_DIR}" install-runtimes
 
     step "Running the LLDB libc++ data formatter tests"
-    ${NINJA} -vC "${BUILD_DIR}" lldb-api-test-deps
+    ninja -vC "${BUILD_DIR}" lldb-api-test-deps
     ${BUILD_DIR}/bin/llvm-lit -sv --param dotest-args='--category libc++' "${MONOREPO_ROOT}/lldb/test/API"
 
     ccache -s
@@ -572,10 +547,10 @@ apple-system|apple-system-hardened)
 
     # In the Apple system configuration, we build libc++ and libunwind separately.
     step "Installing libc++ and libc++abi in Apple-system configuration"
-    ${CMAKE} \
+    cmake \
         -S "${MONOREPO_ROOT}/runtimes" \
         -B "${BUILD_DIR}/cxx" \
-        -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+        -GNinja \
         -DCMAKE_BUILD_TYPE=RelWithDebInfo \
         -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}/cxx" \
         -DLLVM_LIT_ARGS="-sv --xunit-xml-output test-results.xml --timeout=1500 --time-tests" \
@@ -588,10 +563,10 @@ apple-system|apple-system-hardened)
         -DLIBCXXABI_TEST_PARAMS="${params}"
 
     step "Installing libunwind in Apple-system configuration"
-    ${CMAKE} \
+    cmake \
         -S "${MONOREPO_ROOT}/runtimes" \
         -B "${BUILD_DIR}/unwind" \
-        -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+        -GNinja \
         -DCMAKE_BUILD_TYPE=RelWithDebInfo \
         -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}/unwind" \
         -DLLVM_LIT_ARGS="-sv --xunit-xml-output test-results.xml --timeout=1500 --time-tests" \
@@ -601,13 +576,13 @@ apple-system|apple-system-hardened)
         -DCMAKE_INSTALL_NAME_DIR="/usr/lib/system"
 
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}/cxx" check-cxx
+    ninja -vC "${BUILD_DIR}/cxx" check-cxx
 
     step "Running the libc++abi tests"
-    ${NINJA} -vC "${BUILD_DIR}/cxx" check-cxxabi
+    ninja -vC "${BUILD_DIR}/cxx" check-cxxabi
 
     step "Running the libunwind tests"
-    ${NINJA} -vC "${BUILD_DIR}/unwind" check-unwind
+    ninja -vC "${BUILD_DIR}/unwind" check-unwind
 ;;
 aarch64)
     clean
@@ -665,13 +640,13 @@ clang-cl-dll)
     # setting when cmake and the test driver does the right thing automatically.
     generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False"
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 ;;
 clang-cl-static)
     clean
     generate-cmake-libcxx-win -DLIBCXX_ENABLE_SHARED=OFF
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 ;;
 clang-cl-no-vcruntime)
     clean
@@ -682,14 +657,14 @@ clang-cl-no-vcruntime)
     generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False" \
                               -DLIBCXX_TEST_CONFIG="llvm-libc++-shared-no-vcruntime-clangcl.cfg.in"
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 ;;
 clang-cl-debug)
     clean
     generate-cmake-libcxx-win -DLIBCXX_TEST_PARAMS="enable_experimental=False" \
                               -DCMAKE_BUILD_TYPE=Debug
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 ;;
 clang-cl-static-crt)
     clean
@@ -698,7 +673,7 @@ clang-cl-static-crt)
     generate-cmake-libcxx-win -DLIBCXX_ENABLE_SHARED=OFF \
                               -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreaded
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
 ;;
 mingw-dll)
     clean
@@ -744,7 +719,7 @@ mingw-incomplete-sysroot)
     # Only test that building succeeds; there's not much extra value in running
     # the tests here, as it would be equivalent to the mingw-dll config above.
     step "Building the runtimes"
-    ${NINJA} -vC "${BUILD_DIR}"
+    ninja -vC "${BUILD_DIR}"
 ;;
 aix)
     clean
@@ -781,7 +756,7 @@ android-ndk-*)
                            -DLIBCXX_TEST_PARAMS="${PARAMS}" \
                            -DLIBCXXABI_TEST_PARAMS="${PARAMS}"
     check-abi-list
-    ${NINJA} -vC "${BUILD_DIR}" install-cxx install-cxxabi
+    ninja -vC "${BUILD_DIR}" install-cxx install-cxxabi
 
     # Start the emulator and make sure we can connect to the adb server running
     # inside of it.
@@ -794,9 +769,9 @@ android-ndk-*)
     adb shell mkdir -p /data/local/tmp/adb_run
     adb push "${BUILD_DIR}/lib/libc++_shared.so" /data/local/tmp/libc++/libc++_shared.so
     step "Running the libc++ tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+    ninja -vC "${BUILD_DIR}" check-cxx
     step "Running the libc++abi tests"
-    ${NINJA} -vC "${BUILD_DIR}" check-cxxabi
+    ninja -vC "${BUILD_DIR}" check-cxxabi
 ;;
 #################################################################
 # Insert vendor-specific internal configurations below.
diff --git a/llvm/include/llvm/ADT/StringSwitch.h b/llvm/include/llvm/ADT/StringSwitch.h
index 53ebec1eb3a54..5da6076c27390 100644
--- a/llvm/include/llvm/ADT/StringSwitch.h
+++ b/llvm/include/llvm/ADT/StringSwitch.h
@@ -158,7 +158,7 @@ class StringSwitch {
 
   StringSwitch &EndsWithLower(StringLiteral S, T Value) {
     if (!Result && Str.ends_with_insensitive(S))
-      Result = Value;
+      Result = std::move(Value);
 
     return *this;
   }
diff --git a/llvm/lib/ExecutionEngine/Orc/TargetProcess/LibraryScanner.cpp b/llvm/lib/ExecutionEngine/Orc/TargetProcess/LibraryScanner.cpp
index 32f6dbefb8480..96f0b66adec92 100644
--- a/llvm/lib/ExecutionEngine/Orc/TargetProcess/LibraryScanner.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/TargetProcess/LibraryScanner.cpp
@@ -768,7 +768,7 @@ std::string LibraryScanHelper::resolveCanonical(StringRef Path,
 PathType LibraryScanHelper::classifyKind(StringRef Path) const {
   // Detect home directory
   const char *Home = getenv("HOME");
-  if (Home && Path.find(Home) == 0)
+  if (Home && Path.starts_with(Home))
     return PathType::User;
 
   static const std::array<std::string, 5> UserPrefixes = {
@@ -780,7 +780,7 @@ PathType LibraryScanHelper::classifyKind(StringRef Path) const {
   };
 
   for (const auto &Prefix : UserPrefixes) {
-    if (Path.find(Prefix) == 0)
+    if (Path.starts_with(Prefix))
       return PathType::User;
   }
 
diff --git a/llvm/lib/ObjectYAML/CodeViewYAMLSymbols.cpp b/llvm/lib/ObjectYAML/CodeViewYAMLSymbols.cpp
index 3056251809308..5dd10f402f2ca 100644
--- a/llvm/lib/ObjectYAML/CodeViewYAMLSymbols.cpp
+++ b/llvm/lib/ObjectYAML/CodeViewYAMLSymbols.cpp
@@ -80,15 +80,14 @@ void ScalarEnumerationTraits<SymbolKind>::enumeration(IO &io,
                                                       SymbolKind &Value) {
   auto SymbolNames = getSymbolTypeNames();
   for (const auto &E : SymbolNames)
-    io.enumCase(Value, E.Name.str().c_str(), E.Value);
+    io.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarBitSetTraits<CompileSym2Flags>::bitset(IO &io,
                                                   CompileSym2Flags &Flags) {
   auto FlagNames = getCompileSym2FlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<CompileSym2Flags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<CompileSym2Flags>(E.Value));
   }
 }
 
@@ -96,40 +95,35 @@ void ScalarBitSetTraits<CompileSym3Flags>::bitset(IO &io,
                                                   CompileSym3Flags &Flags) {
   auto FlagNames = getCompileSym3FlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<CompileSym3Flags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<CompileSym3Flags>(E.Value));
   }
 }
 
 void ScalarBitSetTraits<ExportFlags>::bitset(IO &io, ExportFlags &Flags) {
   auto FlagNames = getExportSymFlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<ExportFlags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<ExportFlags>(E.Value));
   }
 }
 
 void ScalarBitSetTraits<PublicSymFlags>::bitset(IO &io, PublicSymFlags &Flags) {
   auto FlagNames = getPublicSymFlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<PublicSymFlags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<PublicSymFlags>(E.Value));
   }
 }
 
 void ScalarBitSetTraits<LocalSymFlags>::bitset(IO &io, LocalSymFlags &Flags) {
   auto FlagNames = getLocalFlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<LocalSymFlags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<LocalSymFlags>(E.Value));
   }
 }
 
 void ScalarBitSetTraits<ProcSymFlags>::bitset(IO &io, ProcSymFlags &Flags) {
   auto FlagNames = getProcSymFlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<ProcSymFlags>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<ProcSymFlags>(E.Value));
   }
 }
 
@@ -137,15 +131,14 @@ void ScalarBitSetTraits<FrameProcedureOptions>::bitset(
     IO &io, FrameProcedureOptions &Flags) {
   auto FlagNames = getFrameProcSymFlagNames();
   for (const auto &E : FlagNames) {
-    io.bitSetCase(Flags, E.Name.str().c_str(),
-                  static_cast<FrameProcedureOptions>(E.Value));
+    io.bitSetCase(Flags, E.Name, static_cast<FrameProcedureOptions>(E.Value));
   }
 }
 
 void ScalarEnumerationTraits<CPUType>::enumeration(IO &io, CPUType &Cpu) {
   auto CpuNames = getCPUTypeNames();
   for (const auto &E : CpuNames) {
-    io.enumCase(Cpu, E.Name.str().c_str(), static_cast<CPUType>(E.Value));
+    io.enumCase(Cpu, E.Name, static_cast<CPUType>(E.Value));
   }
 }
 
@@ -177,7 +170,7 @@ void ScalarEnumerationTraits<RegisterId>::enumeration(IO &io, RegisterId &Reg) {
     RegNames = getRegisterNames(*CpuType);
 
   for (const auto &E : RegNames) {
-    io.enumCase(Reg, E.Name.str().c_str(), static_cast<RegisterId>(E.Value));
+    io.enumCase(Reg, E.Name, static_cast<RegisterId>(E.Value));
   }
   io.enumFallback<Hex16>(Reg);
 }
@@ -186,8 +179,7 @@ void ScalarEnumerationTraits<TrampolineType>::enumeration(
     IO &io, TrampolineType &Tramp) {
   auto TrampNames = getTrampolineNames();
   for (const auto &E : TrampNames) {
-    io.enumCase(Tramp, E.Name.str().c_str(),
-                static_cast<TrampolineType>(E.Value));
+    io.enumCase(Tramp, E.Name, static_cast<TrampolineType>(E.Value));
   }
 }
 
@@ -195,7 +187,7 @@ void ScalarEnumerationTraits<ThunkOrdinal>::enumeration(IO &io,
                                                         ThunkOrdinal &Ord) {
   auto ThunkNames = getThunkOrdinalNames();
   for (const auto &E : ThunkNames) {
-    io.enumCase(Ord, E.Name.str().c_str(), static_cast<ThunkOrdinal>(E.Value));
+    io.enumCase(Ord, E.Name, static_cast<ThunkOrdinal>(E.Value));
   }
 }
 
@@ -203,8 +195,7 @@ void ScalarEnumerationTraits<FrameCookieKind>::enumeration(
     IO &io, FrameCookieKind &FC) {
   auto ThunkNames = getFrameCookieKindNames();
   for (const auto &E : ThunkNames) {
-    io.enumCase(FC, E.Name.str().c_str(),
-                static_cast<FrameCookieKind>(E.Value));
+    io.enumCase(FC, E.Name, static_cast<FrameCookieKind>(E.Value));
   }
 }
 
@@ -212,8 +203,7 @@ void ScalarEnumerationTraits<JumpTableEntrySize>::enumeration(
     IO &io, JumpTableEntrySize &FC) {
   auto ThunkNames = getJumpTableEntrySizeNames();
   for (const auto &E : ThunkNames) {
-    io.enumCase(FC, E.Name.str().c_str(),
-                static_cast<JumpTableEntrySize>(E.Value));
+    io.enumCase(FC, E.Name, static_cast<JumpTableEntrySize>(E.Value));
   }
 }
 
diff --git a/llvm/lib/ObjectYAML/DXContainerYAML.cpp b/llvm/lib/ObjectYAML/DXContainerYAML.cpp
index 5dff9bad12b52..5019298baebbd 100644
--- a/llvm/lib/ObjectYAML/DXContainerYAML.cpp
+++ b/llvm/lib/ObjectYAML/DXContainerYAML.cpp
@@ -589,55 +589,55 @@ void MappingTraits<DXContainerYAML::SignatureElement>::mapping(
 void ScalarEnumerationTraits<dxbc::PSV::SemanticKind>::enumeration(
     IO &IO, dxbc::PSV::SemanticKind &Value) {
   for (const auto &E : dxbc::PSV::getSemanticKinds())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::PSV::ComponentType>::enumeration(
     IO &IO, dxbc::PSV::ComponentType &Value) {
   for (const auto &E : dxbc::PSV::getComponentTypes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::PSV::InterpolationMode>::enumeration(
     IO &IO, dxbc::PSV::InterpolationMode &Value) {
   for (const auto &E : dxbc::PSV::getInterpolationModes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::PSV::ResourceType>::enumeration(
     IO &IO, dxbc::PSV::ResourceType &Value) {
   for (const auto &E : dxbc::PSV::getResourceTypes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::PSV::ResourceKind>::enumeration(
     IO &IO, dxbc::PSV::ResourceKind &Value) {
   for (const auto &E : dxbc::PSV::getResourceKinds())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::D3DSystemValue>::enumeration(
     IO &IO, dxbc::D3DSystemValue &Value) {
   for (const auto &E : dxbc::getD3DSystemValues())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::SigMinPrecision>::enumeration(
     IO &IO, dxbc::SigMinPrecision &Value) {
   for (const auto &E : dxbc::getSigMinPrecisions())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::SigComponentType>::enumeration(
     IO &IO, dxbc::SigComponentType &Value) {
   for (const auto &E : dxbc::getSigComponentTypes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::RootParameterType>::enumeration(
     IO &IO, dxbc::RootParameterType &Value) {
   for (const auto &E : dxbc::getRootParameterTypes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxil::ResourceClass>::enumeration(
@@ -650,37 +650,37 @@ void ScalarEnumerationTraits<dxil::ResourceClass>::enumeration(
   };
 
   for (const auto &E : ResourceClasses)
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::SamplerFilter>::enumeration(
     IO &IO, dxbc::SamplerFilter &Value) {
   for (const auto &E : dxbc::getSamplerFilters())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::StaticBorderColor>::enumeration(
     IO &IO, dxbc::StaticBorderColor &Value) {
   for (const auto &E : dxbc::getStaticBorderColors())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::TextureAddressMode>::enumeration(
     IO &IO, dxbc::TextureAddressMode &Value) {
   for (const auto &E : dxbc::getTextureAddressModes())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::ShaderVisibility>::enumeration(
     IO &IO, dxbc::ShaderVisibility &Value) {
   for (const auto &E : dxbc::getShaderVisibility())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 void ScalarEnumerationTraits<dxbc::ComparisonFunc>::enumeration(
     IO &IO, dxbc::ComparisonFunc &Value) {
   for (const auto &E : dxbc::getComparisonFuncs())
-    IO.enumCase(Value, E.Name.str().c_str(), E.Value);
+    IO.enumCase(Value, E.Name, E.Value);
 }
 
 } // namespace yaml
diff --git a/llvm/lib/Target/NVPTX/NVPTX.h b/llvm/lib/Target/NVPTX/NVPTX.h
index 1e0f747f8f7fc..95fd05f2a926f 100644
--- a/llvm/lib/Target/NVPTX/NVPTX.h
+++ b/llvm/lib/Target/NVPTX/NVPTX.h
@@ -66,7 +66,6 @@ void initializeNVPTXCtorDtorLoweringLegacyPass(PassRegistry &);
 void initializeNVPTXLowerAggrCopiesPass(PassRegistry &);
 void initializeNVPTXLowerAllocaPass(PassRegistry &);
 void initializeNVPTXLowerUnreachablePass(PassRegistry &);
-void initializeNVPTXCtorDtorLoweringLegacyPass(PassRegistry &);
 void initializeNVPTXLowerArgsLegacyPassPass(PassRegistry &);
 void initializeNVPTXProxyRegErasurePass(PassRegistry &);
 void initializeNVPTXForwardParamsPassPass(PassRegistry &);
diff --git a/llvm/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp b/llvm/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
index c734d3d430073..7f190f33da808 100644
--- a/llvm/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
@@ -28,10 +28,6 @@
 
 using namespace llvm;
 
-namespace llvm {
-void initializeGenericToNVVMLegacyPassPass(PassRegistry &);
-}
-
 namespace {
 class GenericToNVVM {
 public:
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h b/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
index ee575e3527673..0e913fb1ee669 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
@@ -211,8 +211,8 @@ template <> struct CustomMappingTraits<BBNumberMap> {
   }
 
   static void output(IO &YamlIO, BBNumberMap &SrcToUnwindDest) {
-    for (auto KV : SrcToUnwindDest)
-      YamlIO.mapRequired(std::to_string(KV.first).c_str(), KV.second);
+    for (auto [Src, Dest] : SrcToUnwindDest)
+      YamlIO.mapRequired(std::to_string(Src), Dest);
   }
 };