rocm-sdk: import-test shipped Python extensions + resolve abi3 vs Python <3.12 support

[davidd-amd]

Decision (recorded)

We will not contort the product to accommodate a test-only dependency like rocisa. It remains a known sharp edge.

• rocisa (_rocisa.abi3.so, nanobind STABLE_ABI → CPython 3.12+ only) ships in rocm-sdk-libraries but is test/codegen-only; it is not a supported runtime import for SDK consumers.
• Python 3.10/3.11 are a hard requirement for the product, and abi3 cannot cover them. Rather than per-version builds or packaging changes for a test-only dep, we accept that rocisa is not importable on 3.10/3.11 and leave it as-is.
• The [tensilelite] Re-apply test component config and fix PyTorch SDK test failure #5529 change — testSharedLibrariesLoad skipping .abi3.so / .cpython-* extensions — is the accepted accommodation. It stays.

Why this is acceptable here (and the boundary)

The skip + sharp-edge is tolerable only because rocisa is test-only. The leniency must NOT be read as license to ship unimportable extensions generally:

• A runtime-required Python extension shipped to SDK consumers must be importable on all supported Pythons (3.10–3.14). For nanobind that means per-version builds (abi3 alone is 3.12+).
• A test/build-only extension may either remain a documented sharp edge (rocisa) or be excluded from the version-agnostic runtime wheel (the pattern origami uses).

Remaining (small) work

1. Document the sharp edge: note that rocisa is test/codegen-only and not importable on Python < 3.12; consumers must not depend on importing it at runtime on 3.10/3.11.
2. Record the policy above (runtime extensions → per-version / import-testable on all supported Pythons; test-only → sharp edge or excluded) somewhere durable (packaging docs).
3. The ctypes.CDLL skip in libraries_test.py stands; do not convert it into an importlib import for rocisa (that would force the declined product changes).

Context

• Surfaced during the origami reland ([origami] add origami to mathlibs #5650), which keeps its (non-abi3) extension test-only / excluded from the SDK — the correct pattern given 3.10/3.11 are required.
• Related: [tensilelite] Re-apply test component config and fix PyTorch SDK test failure #5529 (the accepted ctypes.CDLL skip + rocisa stable-ABI test), rocisa ROCISA_USE_STABLE_ABI.

[ScottTodd]

Yes, Python 3.10 and 3.11 support is still required for ROCm, and PyTorch.

[stellaraccident]

We aren't going to contort the entire product to accommodate a test only dep like rocisa. It'll just need to remain a sharp edge.