[Bug]: Outdated binaries when re-building vLLM from source

[DarkLight1337]

🐛 Describe the bug

After upgrading vLLM (e.g. syncing a fork with latest main branch), re-building from source fails to clear/overwrite the existing compiled binaries, resulting in errors such as

AttributeError: '_OpNamespace' '_C' object has no attribute ...

Workaround

Installing from a fresh clone of vLLM fixes this error.

Nevertheless, it would be ideal to automatically remove/update outdated binaries when re-building vLLM.

Related issues

• [Bug]: AttributeError: '_OpNamespace' '_C_cache_ops' object has no attribute 'reshape_and_cache_flash' #5448
• [Bug]: 0.5.0 AttributeError: '_OpNamespace' '_C' object has no attribute 'rms_norm' #5454
• [Bug]: Torch2.3 run fail #5461

[mgoin]

This can be manually addressed by clearing any existing built libraries in vllm with rm vllm/_C* vllm/_moe_C.*

[youkaichao]

it would be ideal to automatically remove/update outdated binaries when re-building vLLM

Users might feel unhappy when we silently delete their files.

I added some hints for users, and users can follow the instruction to do the cleanup.

Let me know if you like this idea.

[Trangle]

It worked.