Issue #18440 has been updated by byroot (Jean Boussier). For what it's worth, I would expect `--yjit-*` options not to turn on YJIT. I agree that it's surprising, I would expect only `--yjit` or `RUBY_YJIT_ENABLE=1` to actually enable it. ---------------------------------------- Feature #18440: YJIT is enabled if any YJIT tuning options are set https://bugs.ruby-lang.org/issues/18440#change-104378 * Author: georgeclaghorn (George Claghorn) * Status: Feedback * Priority: Normal ---------------------------------------- I was testing YJIT in a Rails app with `RUBYOPT="--yjit --yjit-exec-mem-size=32"`. I saw some weird issues around Rails view caching, so I attempted to temporarily disable YJIT by removing `--yjit` and leaving the tuning options in place (`RUBYOPT="--yjit-exec-mem-size=32"`). However, YJIT remained enabled until I also removed `--yjit-exec-mem-size=32`. ``` $ ruby -e 'puts RubyVM::YJIT.runtime_stats.inspect' nil $ ruby --yjit-exec-mem-size -e 'puts RubyVM::YJIT.runtime_stats.inspect' {:inline_code_size=>378495, :outlined_code_size=>311079} ``` I expected removing `--yjit` to disable YJIT and was surprised by this. -- https://bugs.ruby-lang.org/