Cannot install on Windows - Aiter path too long
Author: mykeehuCreated Sep 5, 2026Updated Sep 5, 2026
I can't install it on Windows, even though I'm installing it in the root directory. I run this command: git clone --recursive https://github.com/Dao-AILab/flash-attention.git
And I get this error because of Aiter, LongPath is enabled in the registry:
I:\>git clone --recursive https://github.com/Dao-AILab/flash-attention.git
Cloning into 'flash-attention'...
remote: Enumerating objects: 15615, done.
remote: Counting objects: 100% (358/358), done.
remote: Compressing objects: 100% (213/213), done.
remote: Total 15615 (delta 277), reused 145 (delta 145), pack-reused 15257 (from 2)
Receiving objects: 100% (15615/15615), 21.74 MiB | 26.59 MiB/s, done.
Resolving deltas: 100% (11959/11959), done.
Submodule 'csrc/composable_kernel' (https://github.com/ROCm/composable_kernel.git) registered for path 'csrc/composable_kernel'
Submodule 'csrc/cutlass' (https://github.com/NVIDIA/cutlass.git) registered for path 'csrc/cutlass'
Submodule 'third_party/aiter' (https://github.com/ROCm/aiter.git) registered for path 'third_party/aiter'
Cloning into 'I:/flash-attention/csrc/composable_kernel'...
remote: Enumerating objects: 169834, done.
remote: Counting objects: 100% (6921/6921), done.
remote: Compressing objects: 100% (1270/1270), done.
remote: Total 169834 (delta 6124), reused 5730 (delta 5648), pack-reused 162913 (from 2)
Receiving objects: 100% (169834/169834), 166.43 MiB | 35.92 MiB/s, done.
Resolving deltas: 100% (118464/118464), done.
Cloning into 'I:/flash-attention/csrc/cutlass'...
remote: Enumerating objects: 46338, done.
remote: Counting objects: 100% (178/178), done.
remote: Compressing objects: 100% (129/129), done.
remote: Total 46338 (delta 99), reused 49 (delta 49), pack-reused 46160 (from 3)
Receiving objects: 100% (46338/46338), 73.29 MiB | 32.83 MiB/s, done.
Resolving deltas: 100% (34605/34605), done.
Cloning into 'I:/flash-attention/third_party/aiter'...
remote: Enumerating objects: 132996, done.
remote: Counting objects: 100% (3440/3440), done.
remote: Compressing objects: 100% (1205/1205), done.
remote: Total 132996 (delta 2944), reused 2354 (delta 2188), pack-reused 129556 (from 2)
Receiving objects: 100% (132996/132996), 120.17 MiB | 29.30 MiB/s, done.
Resolving deltas: 100% (104107/104107), done.
Submodule path 'csrc/composable_kernel': checked out 'c56c6750d0fc54ed771d532cc92c316423449614'
Submodule path 'csrc/cutlass': checked out '7127592069c2fe01b041e174ba4345ef9b279671'
Submodule path 'third_party/aiter': checked out '9bab8388c35936814a659b4ebd245c491e1b940a'
Submodule '3rdparty/composable_kernel' (https://github.com/ROCm/composable_kernel.git) registered for path 'third_party/aiter/3rdparty/composable_kernel'
Cloning into 'I:/flash-attention/third_party/aiter/3rdparty/composable_kernel'...
remote: Enumerating objects: 169834, done.
remote: Counting objects: 100% (6921/6921), done.
remote: Compressing objects: 100% (1270/1270), done.
remote: Total 169834 (delta 6124), reused 5730 (delta 5648), pack-reused 162913 (from 2)
Receiving objects: 100% (169834/169834), 166.43 MiB | 31.13 MiB/s, done.
Resolving deltas: 100% (118464/118464), done.
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_kpadding_instance_part1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_kpadding_instance_part2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_default_instance_part1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_default_instance_part2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_default_instance_part3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_bf16/device_gemm_multiply_multiply_xdl_f8_f8_bf16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_default_instance_part1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_default_instance_part2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_default_instance_part3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_multiply_multiply/device_gemm_multiply_multiply_xdl_f8_f8_f16/device_gemm_multiply_multiply_xdl_f8_f8_f16_mk_nk_mn_comp_mfma16x16_kpadding_instance_part3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_batched/device_batched_gemm_xdl_universal_bf16_bf16_bf16/device_batched_gemm_xdl_universal_bf16_bf16_bf16_mk_nk_mn_comp_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_batched/device_batched_gemm_xdl_universal_bf16_bf16_bf16/device_batched_gemm_xdl_universal_bf16_bf16_bf16_mk_nk_mn_mem_v1_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_batched/device_batched_gemm_xdl_universal_bf16_bf16_bf16/device_batched_gemm_xdl_universal_bf16_bf16_bf16_mk_nk_mn_mem_v2_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_bf16/device_gemm_wmma_universal_preshuffle_f8_f8_bf16_mk_wmma_mn_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_bf16/device_gemm_wmma_universal_preshuffle_f8_f8_bf16_mk_wmma_mn_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_bf16/device_gemm_wmma_universal_preshuffle_f8_f8_bf16_mk_wmma_mn_default_instance_p3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_bf16/device_gemm_wmma_universal_preshuffle_f8_f8_bf16_mk_wmma_mn_default_instance_p4.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_f16/device_gemm_wmma_universal_preshuffle_f8_f8_f16_mk_wmma_mn_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_f16/device_gemm_wmma_universal_preshuffle_f8_f8_f16_mk_wmma_mn_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_f16/device_gemm_wmma_universal_preshuffle_f8_f8_f16_mk_wmma_mn_default_instance_p3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_wmma_universal_preshuffle_f8_f8_f16/device_gemm_wmma_universal_preshuffle_f8_f8_f16_mk_wmma_mn_default_instance_p4.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p4.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p5.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma16x16_nk_mn_comp_default_instance_p6.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_mn_p1_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_mn_p2_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_mn_p3_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_mn_p4_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_mn_p5_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_nk_mn_comp_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_bf16_mk_mfma_nk_mn_comp_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_f8_bf16_mk_mfma32x32_mn_comp_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_bf16/device_gemm_xdl_universal_preshuffle_f8_f8_f8_bf16_mk_mfma32x32_mn_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p3.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p4.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p5.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma16x16_mn_compute_default_instance_p6.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_compute_default_instance_p1.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_compute_default_instance_p2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p1_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p1_default_instance_v2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p2_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p2_default_instance_v2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p3_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p3_default_instance_v2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p4_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p4_default_instance_v2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p5_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_preshuffle/device_gemm_xdl_universal_preshuffle_f8_f8_f16/device_gemm_universal_preshuffle_xdl_f8_f8_f16_mk_mfma_mn_p5_default_instance_v2.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_comp_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_comp_kpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_comp_mnkpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_comp_mnpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_mem_v1_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_mem_v1_kpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_mem_v1_mnkpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_mem_v2_default_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpu/gemm_universal_streamk/device_gemm_xdl_universal_streamk_bf16_bf16_bf16/device_gemm_xdl_universal_streamk_bf16_bf16_bf16_km_kn_mn_mem_v2_kpadding_instance.cpp: Filename too long
error: unable to create file library/src/tensor_operation_instance/gpuSource: Dao-AILab/flash-attention