diff --git a/.ci/scripts/check_c10_sync.sh b/.ci/scripts/check_c10_sync.sh
new file mode 100755
index 00000000000..1b4b2aabdf6
--- /dev/null
+++ b/.ci/scripts/check_c10_sync.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+set -exu
+ls pytorch/.git || git clone https://github.com/pytorch/pytorch.git
+pushd pytorch
+git checkout "$(< ../.ci/docker/ci_commit_pins/pytorch.txt)"
+popd
+"$(dirname "${BASH_SOURCE[0]}")"/diff_c10_mirror_with_pytorch.sh
diff --git a/.ci/scripts/compare_dirs.sh b/.ci/scripts/compare_dirs.sh
new file mode 100755
index 00000000000..6b6e3a6cc93
--- /dev/null
+++ b/.ci/scripts/compare_dirs.sh
@@ -0,0 +1,54 @@
+#!/bin/bash
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+set -eux
+
+# Check if dir1's files are also found in dir2 with the same
+# contents. Exempt files named BUCK, CMakeLists.txt, TARGETS, or
+# targets.bzl.
+
+if [ $# -ne 2 ]; then
+    echo "Usage: $0 dir1 dir2" >&2
+    exit 1
+fi
+dir1="$1"
+dir2="$2"
+
+if [ ! -d "$dir1" ] || [ ! -d "$dir2" ]; then
+    echo "Error: Both directories must exist" >&2
+    exit 1
+fi
+
+exit_status=0
+while IFS= read -r -d '' file; do
+    base=$(basename "$file")
+    case "$base" in
+        "BUCK"|"CMakeLists.txt"|"TARGETS"|"targets.bzl")
+            continue
+            ;;
+    esac
+    # Construct the corresponding path in the second directory
+    file2="$dir2/${file#$dir1/}"
+    # Check if the corresponding file exists in the second directory
+    if [ ! -f "$file2" ]; then
+        echo "Error: File '$file' found in '$dir1' but not found in '$dir2'" >&2
+        exit 1
+    fi
+    # Compare the contents of the two files using diff
+    set +ex
+    differences=$(diff -u -p "$file" "$file2")
+    set -e # leave x off
+    # If there are any differences, print an error message and exit with failure status
+    if [ -n "$differences" ]; then
+        echo "Error: Mismatch detected in file '$file':" >&2
+        echo "$differences" >&2
+        exit_status=1
+    fi
+    set -x
+done < <(find "$dir1" -type f -print0)
+
+exit $exit_status
diff --git a/.ci/scripts/diff_c10_mirror_with_pytorch.sh b/.ci/scripts/diff_c10_mirror_with_pytorch.sh
new file mode 100755
index 00000000000..f0694fe8503
--- /dev/null
+++ b/.ci/scripts/diff_c10_mirror_with_pytorch.sh
@@ -0,0 +1,8 @@
+#!/bin/bash
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+$(dirname "${BASH_SOURCE[0]}")/compare_dirs.sh runtime/core/portable_type/c10/c10 pytorch/c10
diff --git a/.github/workflows/check-c10-sync.yml b/.github/workflows/check-c10-sync.yml
new file mode 100644
index 00000000000..cca4a6bf2f2
--- /dev/null
+++ b/.github/workflows/check-c10-sync.yml
@@ -0,0 +1,32 @@
+name: check-c10-sync
+
+on:
+  pull_request:
+    paths:
+      - .ci/docker/ci_commit_pins/pytorch.txt
+      - .ci/scripts/compare_dirs.sh
+      - .ci/scripts/diff_c10_mirror_with_pytorch.sh
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.sha }}-${{ github.event_name == 'workflow_dispatch' }}-${{ github.event_name == 'schedule' }}
+  cancel-in-progress: true
+
+jobs:
+  check-c10-sync:
+    permissions:
+      id-token: write
+      contents: read
+    name: check-c10-sync
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - name: Clone PyTorch
+        run: |
+          set -ex
+          git clone https://github.com/pytorch/pytorch.git
+          pushd pytorch || return
+          git checkout "$(< ../.ci/docker/ci_commit_pins/pytorch.txt)"
+          popd
+          .ci/scripts/check_c10_sync.sh
diff --git a/runtime/core/portable_type/c10/c10/macros/Macros.h b/runtime/core/portable_type/c10/c10/macros/Macros.h
index 919eb6c8567..1429eda2acb 100644
--- a/runtime/core/portable_type/c10/c10/macros/Macros.h
+++ b/runtime/core/portable_type/c10/c10/macros/Macros.h
@@ -241,7 +241,7 @@ using namespace c10::xpu;
 #ifdef __HIPCC__
 // Unlike CUDA, HIP requires a HIP header to be included for __host__ to work.
 // We do this #include here so that C10_HOST_DEVICE and friends will Just Work.
-// See https://github.com/ROCm-Developer-Tools/HIP/issues/441
+// See https://github.com/ROCm/hip/issues/441
 #include <hip/hip_runtime.h>
 #endif
 
diff --git a/runtime/core/portable_type/c10/c10/util/Half.h b/runtime/core/portable_type/c10/c10/util/Half.h
index 373881f21e5..b77cf7b1f4a 100644
--- a/runtime/core/portable_type/c10/c10/util/Half.h
+++ b/runtime/core/portable_type/c10/c10/util/Half.h
@@ -243,12 +243,7 @@ C10_HOST_DEVICE inline float fp16_ieee_to_fp32_value(uint16_t h) {
   // const float exp_scale = 0x1.0p-112f;
   constexpr uint32_t scale_bits = (uint32_t)15 << 23;
   float exp_scale_val = 0;
-#if defined(_MSC_VER) && defined(__clang__)
-  __builtin_memcpy(&exp_scale_val, &scale_bits, sizeof(exp_scale_val));
-#else
   std::memcpy(&exp_scale_val, &scale_bits, sizeof(exp_scale_val));
-#endif
-
   const float exp_scale = exp_scale_val;
   const float normalized_value =
       fp32_from_bits((two_w >> 4) + exp_offset) * exp_scale;
diff --git a/runtime/core/portable_type/c10/c10/util/bit_cast.h b/runtime/core/portable_type/c10/c10/util/bit_cast.h
index 380cfa7db1c..c1d2c102886 100644
--- a/runtime/core/portable_type/c10/c10/util/bit_cast.h
+++ b/runtime/core/portable_type/c10/c10/util/bit_cast.h
@@ -3,7 +3,7 @@
 #include <cstring>
 #include <type_traits>
 
-#if __has_include(<bit>) && (defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L)
+#if __has_include(<bit>) && (__cplusplus >= 202002L || (defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L))
 #include <bit>
 #define C10_HAVE_STD_BIT_CAST 1
 #else
diff --git a/runtime/core/portable_type/c10/c10/util/irange.h b/runtime/core/portable_type/c10/c10/util/irange.h
index f5310510099..81104d9568f 100644
--- a/runtime/core/portable_type/c10/c10/util/irange.h
+++ b/runtime/core/portable_type/c10/c10/util/irange.h
@@ -24,7 +24,7 @@ struct integer_iterator {
   using pointer = I*;
   using reference = I&;
 
-  explicit constexpr integer_iterator(I value) : value(value) {}
+  explicit constexpr integer_iterator(I value_) : value(value_) {}
 
   constexpr I operator*() const {
     return value;
@@ -103,7 +103,7 @@ template <
     typename Integer2,
     std::enable_if_t<std::is_integral_v<Integer1>, bool> = true,
     std::enable_if_t<std::is_integral_v<Integer2>, bool> = true>
-constexpr integer_range<Integer2> irange(Integer1 begin, Integer2 end) {
+integer_range<Integer2> irange(Integer1 begin, Integer2 end) {
   // If end<=begin then the range is empty; we can achieve this effect by
   // choosing the larger of {begin, end} as the loop terminator
   return {