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[rocm-libraries] ROCm/rocm-libraries#7786 (commit 7842dfd)

[CK TILE][Windows] add `msvc::no_unique_address` support for
 Windows (#7786)

## Motivation

While building Flash Attention 2 with CK backend, this warning will spam
in every kernel:
```
DEBUG [1/1837] hipcc.exe ...
DEBUG In file included from H:\ROCm\flash-attention\build\fmha_fwd_d32_bf16_batch_b64x64x16x32x32x32_r4x1x1_r4x1x1_w16x16x16_w16x16x16_qr_vr_pssk_nlogits_alibi_mask_lse_ndropout_nskip_nqscale_ntrload_nsink_gfx12.cu:6:
DEBUG In file included from H:\ROCm\flash-attention\csrc\composable_kernel\example\ck_tile\01_fmha\fmha_fwd.hpp:6:
DEBUG In file included from H:\ROCm\flash-attention\csrc\composable_kernel\include\ck_tile/core.hpp:111:
DEBUG H:\ROCm\flash-attention\csrc\composable_kernel\include\ck_tile/core/tensor/tile_scatter_gather.hpp:1246:7: warning: unknown attribute 'no_unique_address' ignored [-Wunknown-attributes]
DEBUG  1246 |     [[no_unique_address]] std::conditional_t<kUseGlobalLoad_, PageIdxArray, gl_field_empty_t>
DEBUG       |       ^~~~~~~~~~~~~~~~~
DEBUG H:\ROCm\flash-attention\csrc\composable_kernel\include\ck_tile/core/tensor/tile_scatter_gather.hpp:1254:7: warning: unknown attribute 'no_unique_address' ignored [-Wunknown-attributes]
DEBUG  1254 |     [[no_unique_address]] std::conditional_t<kUseGlobalLoad_, index_t, gl_field_empty_t>
DEBUG       |       ^~~~~~~~~~~~~~~~~
DEBUG 2 warnings generated when compiling for host.
...
```

## Technical Details

`[[no_unique_address]]` is not working on Windows LLVM, should use
`[[msvc::no_unique_address]]`.

## Test Plan

Build FA2 with CK backend.

## Test Result

No warnings, no errors.

## Submission Checklist

- [x] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

Co-authored-by: Illia Silin <98187287+illsilin@users.noreply.github.com>
A
apophis committed
42c82b093ec277333a444e077cc65c37b97d8510
Parent: e01603b
Committed by assistant-librarian[bot] <assistant-librarian[bot]@users.noreply.github.com> on 6/4/2026, 2:28:12 AM