windows on arm prototyping

[lanluo-nvidia]

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

Type of change

Please delete options that are not relevant and/or add your own.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified

[github-actions]

There are some changes that do not conform to Python style guidelines:

--- /home/runner/work/TensorRT/TensorRT/setup.py	2026-07-30 23:48:26.025839+00:00
+++ /home/runner/work/TensorRT/TensorRT/setup.py	2026-07-30 23:48:54.879033+00:00
@@ -750,11 +750,13 @@

    extension_type = setuptools.Extension if WINDOWS_CROSS_COMPILE else CUDAExtension
    target_torch_root = os.environ.get("TORCHTRT_TARGET_TORCH_ROOT")
    target_cuda_root = os.environ.get("TORCHTRT_TARGET_CUDA_ROOT")
    target_python_root = os.environ.get("TORCHTRT_TARGET_PYTHON_ROOT")
-    if WINDOWS_CROSS_COMPILE and not (target_torch_root and target_cuda_root and target_python_root):
+    if WINDOWS_CROSS_COMPILE and not (
+        target_torch_root and target_cuda_root and target_python_root
+    ):
        raise RuntimeError(
            "Windows ARM64 cross-compilation requires "
            "TORCHTRT_TARGET_TORCH_ROOT and TORCHTRT_TARGET_CUDA_ROOT and TORCHTRT_TARGET_PYTHON_ROOT"
        )

[github-actions]

There are some changes that do not conform to Python style guidelines:

--- /home/runner/work/TensorRT/TensorRT/setup.py	2026-07-30 23:52:04.097184+00:00
+++ /home/runner/work/TensorRT/TensorRT/setup.py	2026-07-30 23:52:32.736195+00:00
@@ -750,11 +750,13 @@

    extension_type = setuptools.Extension if WINDOWS_CROSS_COMPILE else CUDAExtension
    target_torch_root = os.environ.get("TORCHTRT_TARGET_TORCH_ROOT")
    target_cuda_root = os.environ.get("TORCHTRT_TARGET_CUDA_ROOT")
    target_python_root = os.environ.get("TORCHTRT_TARGET_PYTHON_ROOT")
-    if WINDOWS_CROSS_COMPILE and not (target_torch_root and target_cuda_root and target_python_root):
+    if WINDOWS_CROSS_COMPILE and not (
+        target_torch_root and target_cuda_root and target_python_root
+    ):
        raise RuntimeError(
            "Windows ARM64 cross-compilation requires "
            "TORCHTRT_TARGET_TORCH_ROOT and TORCHTRT_TARGET_CUDA_ROOT and TORCHTRT_TARGET_PYTHON_ROOT"
        )