Issue #21865 has been updated by byroot (Jean Boussier). Single script version of the repro: ```ruby t = Thread.new do sleep 1 Process.kill("TERM", $$) end loop do File.open(__FILE__, kwarg: true) {} end ``` ---------------------------------------- Bug #21865: Crash on signal raise https://bugs.ruby-lang.org/issues/21865#change-116289 * Author: dodecadaniel (Daniel Colson) * Status: Open * ruby -v: 4.0.1 * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- This crashes on Ruby 4.0 ``` sh $ ruby -e 'loop { File.open("./test.rb", kwarg: true) {} }'& [1] 93542 $ kill -TERM 93542 [BUG] Segmentation fault at 0x000000000000001f ``` Note the `0x1f` (i.e. 15, which is `Signal.list["TERM"]`). While preparing the exception we pass argc=2, with argv containing the signal class and the fixnum for the TERM. https://github.com/ruby/ruby/blob/86dba8cfaeabb3b86df921da24b3243b9ce4ab2a/t... That eventually gets passed through to https://github.com/ruby/ruby/blob/86dba8cfaeabb3b86df921da24b3243b9ce4ab2a/c..., where we set the signal fixnum as `last` and treat it like a hash. But 0x1f is a fixnum, not a hash, so that crashes. `rb_scan_args_keyword_p` returns true in this case even though `last` is not a hash because kw_flag is `RB_SCAN_ARGS_PASS_CALLED_KEYWORDS` (which I think causes it to look at the last frame to see if keywords were passed, rather than checking whether `last` is a hash. I don't think we push any frames in this case, so it's looking at whatever the last frame before the signal happened to be). Should we still check that it's a hash regardless? I believe the bug was introduced in https://github.com/ruby/ruby/commit/64f508ade8c8535b7d3ecdd217886aa52fddd43c. -- https://bugs.ruby-lang.org/