Issue #20796 has been updated by mame (Yusuke Endoh). I don't have an access to Intel mac, but I think https://github.com/ruby/ruby/pull/11519 has indeed an off-by-one bug. I could reproduce the issue on Linux with valgrind by forcing to use the wrong `memrchr` function. ``` $ valgrind ./miniruby -e 'p ("Barbaz" + "qux"*1000).rindex("barbaz")' ... ==4779== Invalid read of size 1 ==4779== at 0x3B26DE: my_memrchr (string.c:4529) ==4779== by 0x3B26DE: str_rindex (string.c:4558) ==4779== by 0x3CB46B: rb_str_rindex_m (string.c:4699) ==4779== by 0x431A9C: vm_call_cfunc_with_frame_ (vm_insnhelper.c:3794) ==4779== by 0x452D9D: vm_sendish (vm_insnhelper.c:5961) ==4779== by 0x452D9D: vm_exec_core (insns.def:898) ==4779== by 0x4424A4: rb_vm_exec (vm.c:2564) ==4779== by 0x23A004: rb_ec_exec_node (eval.c:281) ==4779== by 0x23C0A8: ruby_run_node (eval.c:319) ==4779== by 0x15FFC5: rb_main (main.c:43) ==4779== by 0x15FFC5: main (main.c:62) ==4779== Address 0x20682b6f is 1 bytes before a block of size 3,007 alloc'd ==4779== at 0x4846828: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so) ==4779== by 0x2614EA: rb_gc_impl_malloc (default.c:8186) ==4779== by 0x3B3FB3: str_new0 (string.c:983) ==4779== by 0x3B8686: rb_str_plus (string.c:2375) ==4779== by 0x4593F3: vm_opt_plus (vm_insnhelper.c:6491) ==4779== by 0x4593F3: vm_exec_core (insns.def:1244) ==4779== by 0x4424A4: rb_vm_exec (vm.c:2564) ==4779== by 0x23A004: rb_ec_exec_node (eval.c:281) ==4779== by 0x23C0A8: ruby_run_node (eval.c:319) ==4779== by 0x15FFC5: rb_main (main.c:43) ==4779== by 0x15FFC5: main (main.c:62) ==4779== ``` https://github.com/ruby/ruby/pull/11923 fixes the off-by-one issue. I am not sure if this change fixes the issue that the OP reports. @tikkss Can you try this patch? ---------------------------------------- Bug #20796: Segmentation fault in rubyzip tests with ruby 3.4.0-preview2~659 e7cb70be4e on x86_64-darwin24 https://bugs.ruby-lang.org/issues/20796#change-110178 * Author: tikkss (Tsutomu Katsube) * Status: Open * ruby -v: ruby 3.4.0dev (2024-09-03T05:25:25Z v3_4_0_preview2~659 e7cb70be4e) [x86_64-darwin24] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- Steps to reproduce --- ```console $ git clone git@github.com:rubyzip/rubyzip $ cd rubyzip $ bundle $ bundle exec rake ``` Expected behavior --- The tests should complete successfully. Actual behavior --- A segmentation fault occurs during the test run. This issue does not occur with ruby 3.4.0-preview1 or other Ruby versions. Console dump --- See attached `crash.log` and `ruby-2024-10-13-071029.ips` for full details ```console $ bundle exec rake TESTOPTS="-v --seed=1" 2>crash.log Run options: -v --seed=1 # Running: ZipFileTest#test_get_output_stream = 0.02 s = . ZipFileTest#test_add_directory = 0.01 s = . ZipFileTest#test_streaming = 0.01 s = . ZipFileTest#test_nonexistant_zip = 0.00 s = . ZipFileTest#test_open_buffer_without_block = 0.00 s = . ZipFileTest#test_rename_to_existing_entry = 0.00 s = . ZipFileTest#test_open_buffer_with_io_and_block = 0.00 s = . ZipFileTest#test_write_buffer = 0.01 s = . ZipFileTest#test_open_buffer_with_stringio = 0.00 s = . ZipFileTest#test_odd_extra_field = 0.00 s = . ZipFileTest#test_add_existing_entry_name = 0.00 s = . ZipFileTest#test_open_buffer_no_op_does_not_change_file = 0.00 s = . ZipFileTest#test_replace = 0.01 s = . ZipFileTest#test_rename = 0.01 s = . ZipFileTest#test_recover_permissions_after_add_files_to_archive = % ``` My environment --- ```console $ gem env RubyGems Environment: - RUBYGEMS VERSION: 3.6.0.dev - RUBY VERSION: 3.4.0 (2024-10-07 patchlevel -1) [x86_64-darwin24] - INSTALLATION DIRECTORY: /Users/zzz/.rbenv/versions/3.4.0-preview2/lib/ruby/gems/3.4.0+0 - USER INSTALLATION DIRECTORY: /Users/zzz/.gem/ruby/3.4.0+0 - RUBY EXECUTABLE: /Users/zzz/.rbenv/versions/3.4.0-preview2/bin/ruby - GIT EXECUTABLE: /usr/local/bin/git - EXECUTABLE DIRECTORY: /Users/zzz/.rbenv/versions/3.4.0-preview2/bin - SPEC CACHE DIRECTORY: /Users/zzz/.gem/specs - SYSTEM CONFIGURATION DIRECTORY: /Users/zzz/.rbenv/versions/3.4.0-preview2/etc - RUBYGEMS PLATFORMS: - ruby - x86_64-darwin-24 - GEM PATHS: - /Users/zzz/.rbenv/versions/3.4.0-preview2/lib/ruby/gems/3.4.0+0 - /Users/zzz/.gem/ruby/3.4.0+0 - GEM CONFIGURATION: - :update_sources => true - :verbose => true - :backtrace => true - :bulk_threshold => 1000 - "gem" => "--no-document" - REMOTE SOURCES: - https://rubygems.org/ - SHELL PATH: - /Users/zzz/.rbenv/versions/3.4.0-preview2/bin - /usr/local/Cellar/rbenv/1.3.0/libexec - /Users/zzz/.local/bin - /Users/zzz/.rbenv/shims - /Users/zzz/.rbenv/bin - /Users/zzz/.nodenv/bin - /Users/zzz/bin - /Users/zzz/.cargo/bin - /usr/local/sbin - /usr/local/bin - /System/Cryptexes/App/usr/bin - /usr/bin - /bin - /usr/sbin - /sbin - /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin - /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin - /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin - /Library/Apple/usr/bin ``` ```console $ cat Gemfile.lock PATH remote: . specs: rubyzip (3.0.0.alpha) GEM remote: https://rubygems.org/ specs: ast (2.4.2) docile (1.4.1) json (2.7.2) language_server-protocol (3.17.0.3) minitest (5.22.3) parallel (1.26.3) parser (3.3.5.0) ast (~> 2.4.1) racc psych (5.1.2) stringio racc (1.8.1) rainbow (3.1.1) rake (13.1.0) rdoc (6.6.3.1) psych (>= 4.0.0) regexp_parser (2.9.2) rexml (3.3.8) rubocop (1.61.0) json (~> 2.3) language_server-protocol (>= 3.17.0) parallel (~> 1.10) parser (>= 3.3.0.2) rainbow (>= 2.2.2, < 4.0) regexp_parser (>= 1.8, < 3.0) rexml (>= 3.2.5, < 4.0) rubocop-ast (>= 1.30.0, < 2.0) ruby-progressbar (~> 1.7) unicode-display_width (>= 2.4.0, < 3.0) rubocop-ast (1.32.3) parser (>= 3.3.1.0) rubocop-performance (1.20.2) rubocop (>= 1.48.1, < 2.0) rubocop-ast (>= 1.30.0, < 2.0) rubocop-rake (0.6.0) rubocop (~> 1.0) ruby-progressbar (1.13.0) simplecov (0.22.0) docile (~> 1.1) simplecov-html (~> 0.11) simplecov_json_formatter (~> 0.1) simplecov-html (0.13.1) simplecov-lcov (0.8.0) simplecov_json_formatter (0.1.4) stringio (3.1.1) unicode-display_width (2.6.0) PLATFORMS ruby x86_64-darwin-24 DEPENDENCIES minitest (~> 5.22.0) rake (~> 13.1.0) rdoc (~> 6.6.2) rubocop (~> 1.61.0) rubocop-performance (~> 1.20.0) rubocop-rake (~> 0.6.0) rubyzip! simplecov (~> 0.22.0) simplecov-lcov (~> 0.8) BUNDLED WITH 2.6.0.dev ``` ---Files-------------------------------- crash.log (74.3 KB) ruby-2024-10-13-071029.ips (31.5 KB) crash.file_test.log (70.2 KB) -- https://bugs.ruby-lang.org/