Segmentation fault when using it var in rescue block in tests

[scarhand]

Steps to reproduce

Can't reproduce it using the generic bug template, only by running rails test in a rails project. I'm probably holding it wrong by using the it block var in a different block scope, but it shouldn't segfault.

class SegfaultTest < ActiveSupport::TestCase
  test "segfaults" do
    [1].each do
      begin
        puts it
      rescue => e
        puts it
      end
    end
  end
end

Rails 7.2.2 repo with the segfaulting test case here: https://github.com/scarhand/rails-test-segfault

Expected behavior

It should raise an error that assertions are missing, but it should not segfault.

Actual behavior

/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:46: [BUG] Segmentation fault at 0x0000000000000001
ruby 3.4.1 (2024-12-25 revision 48d4efcb85) +YJIT +PRISM [x86_64-darwin23]

-- Crash Report log information --------------------------------------------
   See Crash Report log file in one of the following locations:
     * ~/Library/Logs/DiagnosticReports
     * /Library/Logs/DiagnosticReports
   for more details.
Don't forget to include the above Crash Report log file in bug reports.

-- Control frame information -----------------------------------------------
c:0028 p:---- s:0184 e:000183 CFUNC  :to_binary
c:0027 p:0008 s:0180 e:000179 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:46 [FINISH]
c:0026 p:---- s:0174 e:000173 CFUNC  :fetch
c:0025 p:0024 s:0166 e:000165 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:64
c:0024 p:0023 s:0159 e:000158 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:89 [FINISH]
c:0023 p:---- s:0153 e:000152 CFUNC  :require
c:0022 p:0054 s:0148 e:000147 BLOCK  /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82
c:0021 p:0139 s:0141 e:000140 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/load_path_cache/core_ext/kernel_requir [FINISH]
c:0020 p:0057 s:0132 e:000131 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/zeitwerk-2.7.3/lib/zeitwerk/core_ext/kernel.rb:34
c:0019 p:0014 s:0124 e:000123 BLOCK  /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:62 [FINISH]
c:0018 p:---- s:0116 e:000115 CFUNC  :each
c:0017 p:0021 s:0112 e:000111 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:60
c:0016 p:0009 s:0105 e:000104 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:52
c:0015 p:0041 s:0100 e:000099 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/commands/test/test_command.rb:33
c:0014 p:0054 s:0094 e:000093 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor/command.rb:28
c:0013 p:0040 s:0086 e:000085 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor/invocation.rb:127
c:0012 p:0031 s:0079 e:000078 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command/base.rb:178
c:0011 p:0213 s:0072 e:000071 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor.rb:538
c:0010 p:0048 s:0059 e:000058 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command/base.rb:73
c:0009 p:0025 s:0052 e:000051 BLOCK  /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:71
c:0008 p:0015 s:0049 e:000048 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:149
c:0007 p:0048 s:0043 e:000042 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:69
c:0006 p:0038 s:0032 e:000031 TOP    /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/commands.rb:18 [FINISH]
c:0005 p:---- s:0027 e:000026 CFUNC  :require
c:0004 p:0054 s:0022 e:000021 BLOCK  /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82
c:0003 p:0139 s:0015 e:000014 METHOD /Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/load_path_cache/core_ext/kernel_requir
c:0002 p:0024 s:0006 e:000005 EVAL   bin/rails:4 [FINISH]
c:0001 p:0000 s:0003 E:0003b0 DUMMY  [FINISH]

-- Ruby level backtrace information ----------------------------------------
bin/rails:4:in '<main>'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in 'require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82:in 'block (2 levels) in replace_require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82:in 'require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/commands.rb:18:in '<main>'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:69:in 'invoke'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:149:in 'with_argv'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command.rb:71:in 'block in invoke'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command/base.rb:73:in 'perform'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor.rb:538:in 'dispatch'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/command/base.rb:178:in 'invoke_command'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor/invocation.rb:127:in 'invoke_command'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/thor-1.3.2/lib/thor/command.rb:28:in 'run'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/commands/test/test_command.rb:33:in 'perform'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:52:in 'run'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:60:in 'load_tests'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:60:in 'each'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/railties-7.2.2.1/lib/rails/test_unit/runner.rb:62:in 'block in load_tests'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/zeitwerk-2.7.3/lib/zeitwerk/core_ext/kernel.rb:34:in 'require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in 'require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82:in 'block (2 levels) in replace_require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/3.4.0/bundled_gems.rb:82:in 'require'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:89:in 'load_iseq'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:64:in 'fetch'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:64:in 'fetch'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:46:in 'input_to_storage'
/Users/scarhand/.rbenv/versions/3.4.1/lib/ruby/gems/3.4.0/gems/bootsnap-1.18.6/lib/bootsnap/compile_cache/iseq.rb:46:in 'to_binary'

-- Threading information ---------------------------------------------------
Total ractor count: 1
Ruby thread count for this ractor: 2

-- Machine register context ------------------------------------------------
 rax: 0x0000000000000000 rbx: 0x000000010f3bf3c0 rcx: 0x000000010f9a26b0
 rdx: 0x0000000000000000 rdi: 0x0000000000000000 rsi: 0x000000010f3bf3c0
 rbp: 0x00007ff7b0cc0d50 rsp: 0x00007ff7b0cc0d20  r8: 0xffffffffffffffe8
  r9: 0x0000000000000000 r10: 0x0000000000000018 r11: 0xffffffc09c739b4d
 r12: 0x00007ff7b0cc0f08 r13: 0x00007ff7b0cc0f20 r14: 0x0000000000000000
 r15: 0x0000000000000000 rip: 0x000000010fb4dfc0 rfl: 0x0000000000010283

-- C level backtrace information -------------------------------------------
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(rb_vm_bugreport+0x9bd) [0x10fbd9c9d]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(rb_bug_for_fatal_signal+0x148) [0x10f9f4a38]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(sigsegv+0x4e) [0x10fb2f8fe]
/usr/lib/system/libsystem_platform.dylib(_sigtramp+0x1d) [0x7ff8071b325d]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(rb_str_cmp+0x20) [0x10fb4dfc0]
/usr/lib/system/libsystem_c.dylib(_isort+0x87) [0x7ff80702749c]
[0x7ff80704c8b3]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_ruby_qsort+0x2e) [0x10fb97bee]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_ibf_dump_outer_variables+0xfe) [0x10f9a242e]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_ibf_dump_iseq_list_i+0xe0b) [0x10f9a186b]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_st_general_foreach+0xca) [0x10fb38f3a]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_st_foreach+0x33) [0x10fb39653]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_ibf_dump_iseq_list+0x4f) [0x10f97078f]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_iseq_ibf_dump+0x17e) [0x10f97050e]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_vm_call_cfunc_with_frame_+0x134) [0x10fbcaea4]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_vm_exec_core+0x2f58) [0x10fbacaa8]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_vm_exec+0x1ac) [0x10fba86bc]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_funcallv_scope+0x2a4) [0x10fbb89b4]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_funcall+0x2df) [0x10fbb908f]
/Users/scarhand/.rbenv/versions/3.4.1/lib/libruby.3.4.dylib(_rb_protect+0xcb) [0x10fa00e0b]
[0x10f3a24c1]

System configuration

Rails version: 7.2.2

Ruby version: 3.4.1

[Edouard-chin]

Thanks for reporting the issue. I can reproduce with a bare script. I don't know the reason, but in case this helps someone figure it out:

require "tempfile"

file = Tempfile.new("segfault-bug")
file.write(<<~RUBY)
  [1].each do
  rescue => e
    puts it
  end
RUBY
file.rewind

RubyVM::InstructionSequence.compile_file(file.path).to_binary

It sefault on Rails because of bootsnap: https://github.com/Shopify/bootsnap/blob/39ca97ec999ec621f46db7f8d87cdaf2faae8874/lib/bootsnap/compile_cache/iseq.rb#L46

It also segfault on ruby master

[byroot]

Thanks for reporting it, but this is a Ruby bug, and should be reported at: https://bugs.ruby-lang.org/projects/ruby-master/issues

[byroot]

Ticket open at https://bugs.ruby-lang.org/issues/21370