Centralize torch-family version pins in torch_pin.py

torch_pin.py is now the single source of truth for torch + the three
domain libraries (vision/audio/codec). It exposes a CHANNEL field
(nightly/test/release), the four version constants, NIGHTLY_VERSION,
and helpers — torch_spec() / torchaudio_spec() / torchcodec_spec() /
torchvision_spec() emit the right pip spec, torch_index_url_base()
returns the right wheel index, and torch_branch() / torchaudio_branch()
/ torchvision_branch() derive the upstream release/M.N branch from each
package's version. Every consumer — install_requirements.py, the two
install_pytorch.sh / utils.sh shell helpers, test_model_e2e.sh,
test_wheel_package_qnn.sh, the moshi/mimi install_requirements.sh, the
update_pytorch_pin.py script, and the weekly bump workflow — reads
through these helpers instead of re-encoding the version strings.

Switching to a release candidate is now a one-line change (CHANNEL =
"test") plus bumping the four version constants. The header in
torch_pin.py walks through the procedure.

update_pytorch_pin.py imports CHANNEL / NIGHTLY_VERSION / torch_branch
directly (no more regex parsing of the file). For nightly it pins to
an immutable SHA looked up by date; for test/release it writes
torch_branch() (e.g. "release/2.12") into
.ci/docker/ci_commit_pins/pytorch.txt so git checkout follows
cherry-picks as they land.

The weekly-pytorch-pin-bump workflow is guarded on CHANNEL == "nightly"
and uses an in-place re.sub on NIGHTLY_VERSION (the previous
`printf '...' > torch_pin.py` would have clobbered the new constants
and helpers).

test/test_torch_pin.py covers all three channels, all four specs, and
the release/M.N branch derivation.

Co-authored-by: Claude <noreply@anthropic.com>

Author: mergennachin

.ci/docker/common/install_pytorch.sh

@@ -36,10 +36,20 @@ install_pytorch_and_domains() {
   conda_run python setup.py bdist_wheel
   pip_install "$(echo dist/*.whl)"
 
-  # Grab the pinned audio and vision commits from PyTorch
-  TORCHAUDIO_VERSION=$(cat .github/ci_commit_pins/audio.txt)
+  # For nightly, defer to PyTorch's own pinned audio/vision commits.
+  # For test/release, use the release/M.N branch derived from torch_pin.py
+  # (torchaudio_branch() / torchvision_branch()).
+  # We are inside the cloned pytorch/ subdir at this point (see `pushd pytorch`
+  # above), so `cd ..` lands in the executorch repo root where torch_pin.py lives.
+  TORCH_CHANNEL=$(cd .. && python -c "from torch_pin import CHANNEL; print(CHANNEL)")
+  if [ "$TORCH_CHANNEL" = "nightly" ]; then
+    TORCHAUDIO_VERSION=$(cat .github/ci_commit_pins/audio.txt)
+    TORCHVISION_VERSION=$(cat .github/ci_commit_pins/vision.txt)
+  else
+    TORCHAUDIO_VERSION=$(cd .. && python -c "from torch_pin import torchaudio_branch; print(torchaudio_branch())")
+    TORCHVISION_VERSION=$(cd .. && python -c "from torch_pin import torchvision_branch; print(torchvision_branch())")
+  fi
   export TORCHAUDIO_VERSION
-  TORCHVISION_VERSION=$(cat .github/ci_commit_pins/vision.txt)
   export TORCHVISION_VERSION
 
   install_domains

.ci/scripts/test_model_e2e.sh

@@ -260,7 +260,10 @@ if [ "$AUDIO_URL" != "" ]; then
 elif [[ "$MODEL_NAME" == *whisper* ]] || [ "$MODEL_NAME" = "voxtral_realtime" ]; then
   conda install -y -c conda-forge "ffmpeg<8"
   pip install datasets soundfile
-  pip install torchcodec==0.12.0.dev20260409 --extra-index-url https://download.pytorch.org/whl/nightly/cpu
+  # We pushd'd into EXECUTORCH_ROOT above, so torch_pin is importable here.
+  TORCHCODEC_PKG=$(python -c "from torch_pin import torchcodec_spec; print(torchcodec_spec())")
+  TORCHCODEC_INDEX=$(python -c "from torch_pin import torch_index_url_base; print(torch_index_url_base())")
+  pip install "$TORCHCODEC_PKG" --extra-index-url "${TORCHCODEC_INDEX}/cpu"
   python -c "from datasets import load_dataset;import soundfile as sf;sample = load_dataset('distil-whisper/librispeech_long', 'clean', split='validation')[0]['audio'];sf.write('${MODEL_DIR}/$AUDIO_FILE', sample['array'][:sample['sampling_rate']*30], sample['sampling_rate'])"
 fi
 

.ci/scripts/test_wheel_package_qnn.sh

@@ -150,25 +150,26 @@ run_core_tests () {
   echo "=== [$LABEL] Installing wheel & deps ==="
   "$PIPBIN" install --upgrade pip
   "$PIPBIN" install "$WHEEL_FILE"
-  TORCH_VERSION=$(
+  # runpy.run_path uses a relative path, so the caller must run this script
+  # from the executorch repo root (where torch_pin.py lives).
+  TORCH_SPEC=$(
   "$PYBIN" - <<'PY'
 import runpy
 module_vars = runpy.run_path("torch_pin.py")
-print(module_vars["TORCH_VERSION"])
+print(module_vars["torch_spec"]())
 PY
 )
-
-  NIGHTLY_VERSION=$(
+  TORCH_INDEX=$(
   "$PYBIN" - <<'PY'
 import runpy
 module_vars = runpy.run_path("torch_pin.py")
-print(module_vars["NIGHTLY_VERSION"])
+print(module_vars["torch_index_url_base"]())
 PY
 )
-  echo "=== [$LABEL] Install torch==${TORCH_VERSION}.${NIGHTLY_VERSION} ==="
+  echo "=== [$LABEL] Install $TORCH_SPEC from ${TORCH_INDEX}/cpu ==="
 
   # Install torchao based on the pinned PyTorch version
-  "$PIPBIN" install torch=="${TORCH_VERSION}.${NIGHTLY_VERSION}" --index-url "https://download.pytorch.org/whl/nightly/cpu"
+  "$PIPBIN" install "$TORCH_SPEC" --index-url "${TORCH_INDEX}/cpu"
   "$PIPBIN" install wheel
 
   # Install torchao based on the pinned commit from third-party/ao submodule

.ci/scripts/utils.sh

@@ -140,10 +140,20 @@ install_pytorch_and_domains() {
   fi
 
   dedupe_macos_loader_path_rpaths
-  # Grab the pinned audio and vision commits from PyTorch
-  TORCHAUDIO_VERSION=$(cat .github/ci_commit_pins/audio.txt)
+  # For nightly, defer to PyTorch's own pinned audio/vision commits.
+  # For test/release, use the release/M.N branch derived from torch_pin.py
+  # (torchaudio_branch() / torchvision_branch()).
+  # We are inside the cloned pytorch/ subdir at this point (see `pushd pytorch`
+  # above), so `cd ..` lands in the executorch repo root where torch_pin.py lives.
+  TORCH_CHANNEL=$(cd .. && python -c "from torch_pin import CHANNEL; print(CHANNEL)")
+  if [ "$TORCH_CHANNEL" = "nightly" ]; then
+    TORCHAUDIO_VERSION=$(cat .github/ci_commit_pins/audio.txt)
+    TORCHVISION_VERSION=$(cat .github/ci_commit_pins/vision.txt)
+  else
+    TORCHAUDIO_VERSION=$(cd .. && python -c "from torch_pin import torchaudio_branch; print(torchaudio_branch())")
+    TORCHVISION_VERSION=$(cd .. && python -c "from torch_pin import torchvision_branch; print(torchvision_branch())")
+  fi
   export TORCHAUDIO_VERSION
-  TORCHVISION_VERSION=$(cat .github/ci_commit_pins/vision.txt)
   export TORCHVISION_VERSION
 
   install_domains

.github/scripts/update_pytorch_pin.py

@@ -8,6 +8,12 @@
 import urllib.request
 from pathlib import Path
 
+# torch_pin.py lives at the repo root. Locate it relative to this script so
+# the import works regardless of where the script is invoked from.
+_REPO_ROOT = Path(__file__).resolve().parents[2]
+sys.path.insert(0, str(_REPO_ROOT))
+from torch_pin import CHANNEL, NIGHTLY_VERSION, torch_branch
+
 
 def parse_nightly_version(nightly_version):
     """
@@ -27,23 +33,6 @@ def parse_nightly_version(nightly_version):
     return f"{year}-{month}-{day}"
 
 
-def get_torch_nightly_version():
-    """
-    Read NIGHTLY_VERSION from torch_pin.py.
-
-    Returns:
-        NIGHTLY_VERSION string
-    """
-    with open("torch_pin.py", "r") as f:
-        content = f.read()
-
-    match = re.search(r'NIGHTLY_VERSION\s*=\s*["\']([^"\']+)["\']', content)
-    if not match:
-        raise ValueError("Could not find NIGHTLY_VERSION in torch_pin.py")
-
-    return match.group(1)
-
-
 def get_commit_hash_for_nightly(date_str):
     """
     Fetch commit hash from PyTorch nightly branch for a given date.
@@ -91,17 +80,17 @@ def extract_hash_from_title(title):
     return match.group(1)
 
 
-def update_pytorch_pin(commit_hash):
+def update_pytorch_pin(ref):
     """
-    Update .ci/docker/ci_commit_pins/pytorch.txt with the new commit hash.
+    Update .ci/docker/ci_commit_pins/pytorch.txt with the new ref.
 
     Args:
-        commit_hash: Commit hash to write
+        ref: Either a commit SHA (nightly) or a branch name (test/release).
     """
     pin_file = ".ci/docker/ci_commit_pins/pytorch.txt"
     with open(pin_file, "w") as f:
-        f.write(f"{commit_hash}\n")
-    print(f"Updated {pin_file} with commit hash: {commit_hash}")
+        f.write(f"{ref}\n")
+    print(f"Updated {pin_file} with ref: {ref}")
 
 
 def should_skip_file(filename):
@@ -118,18 +107,20 @@ def should_skip_file(filename):
     return filename in skip_files
 
 
-def fetch_file_content(commit_hash, file_path):
+def fetch_file_content(ref, file_path):
     """
     Fetch file content from GitHub API.
 
     Args:
-        commit_hash: Commit hash to fetch from
+        ref: Commit SHA or branch name to fetch from
         file_path: File path in the repository
 
     Returns:
         File content as bytes
     """
-    api_url = f"https://api.github.com/repos/pytorch/pytorch/contents/{file_path}?ref={commit_hash}"
+    api_url = (
+        f"https://api.github.com/repos/pytorch/pytorch/contents/{file_path}?ref={ref}"
+    )
 
     req = urllib.request.Request(api_url)
     req.add_header("Accept", "application/vnd.github.v3+json")
@@ -146,15 +137,15 @@ def fetch_file_content(commit_hash, file_path):
         raise
 
 
-def sync_directory(et_dir, pt_path, commit_hash):
+def sync_directory(et_dir, pt_path, ref):
     """
     Sync files from PyTorch to ExecuTorch using GitHub API.
     Only syncs files that already exist in ExecuTorch - does not add new files.
 
     Args:
         et_dir: ExecuTorch directory path
         pt_path: PyTorch directory path in the repository (e.g., "c10")
-        commit_hash: Commit hash to fetch from
+        ref: Commit SHA or branch name to fetch from
 
     Returns:
         Number of files grafted
@@ -181,12 +172,12 @@ def sync_directory(et_dir, pt_path, commit_hash):
 
         # Fetch content from PyTorch and compare
         try:
-            pt_content = fetch_file_content(commit_hash, pt_file_path)
+            pt_content = fetch_file_content(ref, pt_file_path)
             et_content = et_file.read_bytes()
 
             if pt_content != et_content:
                 print(f"⚠️  Difference detected in {rel_path}")
-                print(f"📋 Grafting from PyTorch commit {commit_hash}...")
+                print(f"📋 Grafting from PyTorch ref {ref}...")
 
                 et_file.write_bytes(pt_content)
                 print(f"✅ Grafted {et_file}")
@@ -201,12 +192,12 @@ def sync_directory(et_dir, pt_path, commit_hash):
     return files_grafted
 
 
-def sync_c10_directories(commit_hash):
+def sync_c10_directories(ref):
     """
     Sync c10 and torch/headeronly directories from PyTorch to ExecuTorch using GitHub API.
 
     Args:
-        commit_hash: PyTorch commit hash to sync from
+        ref: PyTorch commit SHA or branch name to sync from
 
     Returns:
         Total number of files grafted
@@ -231,7 +222,7 @@ def sync_c10_directories(commit_hash):
 
     total_grafted = 0
     for et_dir, pt_path in dir_pairs:
-        files_grafted = sync_directory(et_dir, pt_path, commit_hash)
+        files_grafted = sync_directory(et_dir, pt_path, ref)
         total_grafted += files_grafted
 
     if total_grafted > 0:
@@ -244,27 +235,26 @@ def sync_c10_directories(commit_hash):
 
 def main():
     try:
-        # Read NIGHTLY_VERSION from torch_pin.py
-        nightly_version = get_torch_nightly_version()
-        print(f"Found NIGHTLY_VERSION: {nightly_version}")
-
-        # Parse to date string
-        date_str = parse_nightly_version(nightly_version)
-        print(f"Parsed date: {date_str}")
-
-        # Fetch commit hash from PyTorch nightly branch
-        commit_hash = get_commit_hash_for_nightly(date_str)
-        print(f"Found commit hash: {commit_hash}")
+        print(f"CHANNEL: {CHANNEL}")
+        if CHANNEL == "nightly":
+            # Nightly pins to an immutable SHA looked up by date.
+            print(f"Found NIGHTLY_VERSION: {NIGHTLY_VERSION}")
+            date_str = parse_nightly_version(NIGHTLY_VERSION)
+            print(f"Parsed date: {date_str}")
+            pin_ref = get_commit_hash_for_nightly(date_str)
+        else:
+            # For test/release, pin to the branch name so CI picks up
+            # cherry-picks / security patches as they land on the branch.
+            pin_ref = torch_branch()
+        print(f"Pin ref: {pin_ref}")
 
         # Update the pin file
-        update_pytorch_pin(commit_hash)
+        update_pytorch_pin(pin_ref)
 
-        # Sync c10 directories from PyTorch
-        sync_c10_directories(commit_hash)
+        # Sync c10 directories from PyTorch (ref param accepts branches too)
+        sync_c10_directories(pin_ref)
 
-        print(
-            "\n✅ Successfully updated PyTorch commit pin and synced c10 directories!"
-        )
+        print("\n✅ Successfully updated PyTorch pin and synced c10 directories!")
 
     except Exception as e:
         print(f"Error: {e}", file=sys.stderr)

.github/workflows/weekly-pytorch-pin-bump.yml

@@ -22,29 +22,44 @@ jobs:
         with:
           python-version: '3.11'
 
+      - name: Check torch_pin channel
+        id: channel
+        run: |
+          CHANNEL=$(python -c "from torch_pin import CHANNEL; print(CHANNEL)")
+          echo "channel=${CHANNEL}" >> "$GITHUB_OUTPUT"
+          if [ "${CHANNEL}" != "nightly" ]; then
+            echo "torch_pin.py CHANNEL is '${CHANNEL}'; weekly nightly bump only runs when CHANNEL == 'nightly'."
+          fi
+
       - name: Determine nightly version
+        if: steps.channel.outputs.channel == 'nightly'
         id: nightly
         run: |
           NIGHTLY_DATE=$(date -u -d 'yesterday' '+%Y%m%d')
           NIGHTLY_VERSION="dev${NIGHTLY_DATE}"
           echo "version=${NIGHTLY_VERSION}" >> "$GITHUB_OUTPUT"
 
-      - name: Read current TORCH_VERSION
-        id: torch
-        run: |
-          TORCH_VERSION=$(python -c "exec(open('torch_pin.py').read()); print(TORCH_VERSION)")
-          echo "version=${TORCH_VERSION}" >> "$GITHUB_OUTPUT"
-
       - name: Update torch_pin.py with new NIGHTLY_VERSION
+        if: steps.channel.outputs.channel == 'nightly'
         run: |
-          printf 'TORCH_VERSION = "%s"\nNIGHTLY_VERSION = "%s"\n' \
-            "${{ steps.torch.outputs.version }}" \
-            "${{ steps.nightly.outputs.version }}" > torch_pin.py
+          python -c "
+          import re, pathlib
+          p = pathlib.Path('torch_pin.py')
+          p.write_text(re.sub(
+              r'^NIGHTLY_VERSION\s*=\s*\".*\"$',
+              'NIGHTLY_VERSION = \"${{ steps.nightly.outputs.version }}\"',
+              p.read_text(),
+              count=1,
+              flags=re.MULTILINE,
+          ))
+          "
 
       - name: Run pin bump script
+        if: steps.channel.outputs.channel == 'nightly'
         run: python .github/scripts/update_pytorch_pin.py
 
       - name: Create branch and PR
+        if: steps.channel.outputs.channel == 'nightly'
         env:
           GH_TOKEN: ${{ secrets.UPDATEBOT_TOKEN }}
         run: |

examples/models/moshi/mimi/install_requirements.sh

@@ -7,10 +7,16 @@
 
 set -x
 
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+# torch_pin lives at the executorch repo root.
+cd "$SCRIPT_DIR/../../../.."
+
+TORCHCODEC_PKG=$(python -c "from torch_pin import torchcodec_spec; print(torchcodec_spec())")
+TORCHCODEC_INDEX=$(python -c "from torch_pin import torch_index_url_base; print(torch_index_url_base())")
+
 sudo apt install ffmpeg -y
-pip install torchcodec==0.12.0.dev20260409 --extra-index-url https://download.pytorch.org/whl/nightly/cpu
+pip install "$TORCHCODEC_PKG" --extra-index-url "${TORCHCODEC_INDEX}/cpu"
 pip install moshi==0.2.11
 pip install bitsandbytes soundfile einops
 # Run llama2/install requirements for torchao deps
-SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
 bash "$SCRIPT_DIR"/../../llama/install_requirements.sh