Make build_id.lo more random (#58258) #232
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This does not fix the underlying issue that can occur here which is a collision of build_ids.lo between modules in IR decompression. Fixing that requires a somewhat significant overhaul to the serialization of IR (probably using the module identity as a key). This does mean we use a lot more of the bits available here so it makes collisions a lot less likely( they were already extremely rare) but hrtime does tend to only use the lower bits of a 64 bit integer and this will hopefully add some more randomness and make this even less likely
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Drvi
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May 3, 2025
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PR Description
This does not fix the underlying issue that can occur here which is a collision of build_ids.lo between modules in IR decompression. Fixing that requires a somewhat significant overhaul to the serialization of IR (probably using the module identity as a key). This does mean we use a lot more of the bits available here so it makes collisions a lot less likely( they were already extremely rare) but hrtime does tend to only use the lower bits of a 64 bit integer and this will hopefully add some more randomness and make this even less likely
This also adds a check for collisions when modules are loaded and calls
abort()when a collision is detected.Checklist
Requirements for merging:
port-to-*labels that don't apply.