delete_nonreduced_fuzz_inputs.sh: Use older branches as well? #265

issue maflcko openend this issue on March 12, 2026

maflcko commented at 5:38 pm on March 12, 2026: contributor

Currently, only the (a random) top commit is used in delete_nonreduced_fuzz_inputs.sh: https://github.com/bitcoin-core/qa-assets/blob/b30853a993f2fdc2edb8608b4544164d05312428/delete_nonreduced_fuzz_inputs.sh#L42

It could make sense to use two more previous branches.

That is, when 31.x is about to be branched-off, the script could also merge against 30.x and 29.x, which seems to match the current 18 months EOL policy: https://bitcoincore.org/en/lifecycle/ says that 28.x was released 2024-10-02 and will be EOL after v31.0.

Suggested in #263 (comment)
murchandamus commented at 5:51 pm on March 12, 2026: contributor

And then keep the superset of all the inputs that were not deleted? That sounds like a good idea to me.
sipa commented at 1:38 pm on March 13, 2026: contributor
Yeah, I’m imagining that like the current process:
- First all seeds (for a given fuzz test) are moved to a temporary directory
- For each relevant commit (so the last commit in each of [master, 30.x, 29.x] e.g.):
  
  Compile with and without sanitizers:
  
  Do a set-cover merge from the temporary directory into the real corpus directory
  
  Do the equivalent for AFL or whatever other techniques are supported
- Delete the temporary directory
This will make old inputs expire when they become irrelevant, but still let old branches benefit from new fuzzing work to the extent the fuzz test remains compatible.