Backport #5661: Segfault in Random.rand with Spork gem

• Status: Closed
• Assignee: usa (Usaku NAKAMURA)

[Odaeus (Andrew France)]

When running my Rails 3.1 RSpec suite with the Spork gem I get a Segmentation Fault caused by the Random.rand method.

The full debug output is attached. Sorry I have not been able to isolate the code to a minimum test case. Suggestions on reproducing with less code would be welcome.

The offending code is in a Factory Girl factory definition:

trait :with_messages do
after_create do |mt|
user = FactoryGirl.create(:user) # To prevent creating 1 user per message
FactoryGirl.create_list(:message, 1 + Random.rand(4), thread: mt, created_by: user)
end
end

Spork is loaded with: bundle exec spork rspec
The fault occurs when the test run is executed with: bundle exec rspec spec
It works fine when not running in the Spork process.

[Odaeus (Andrew France)]

Sigh, sorry I appear to have used a bad formatter code and can't edit the ticket.

[normalperson (Eric Wong)]

• File 0001-random.c-random_s_rand-avoid-segfault-after-fork-rub.patch 0001-random.c-random_s_rand-avoid-segfault-after-fork-rub.patch added

Attached patch should fix it (test cases included).
git users: git pull git://bogomips.org/ruby.git random-fork

Until the next Ruby release, Spork can workaround this by using
"rand(4)" instead of "Random.rand(4)"

[nahi (Hiroshi Nakamura)]

formatting

[ko1 (Koichi Sasada)]

• Category set to core
• Assignee set to nahi (Hiroshi Nakamura)

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r34977.
Andrew, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

• random.c (random_s_rand): ensure default PRNG is re-initialized
  after fork. patched by Eric Wong. [ruby-core:41209][Bug #5661]

[nobu (Nobuyoshi Nakada)]

• Tracker changed from Bug to Backport
• Project changed from Ruby master to Backport193
• Category deleted (core)
• Status changed from Closed to Assigned
• Assignee changed from nahi (Hiroshi Nakamura) to usa (Usaku NAKAMURA)

[usa (Usaku NAKAMURA)]

• Status changed from Assigned to Closed

This issue was solved with changeset r37208.
Andrew, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

merge revision(s) 34977: [Backport #5661]

* random.c (random_s_rand): ensure default PRNG is re-initialized
  after fork.  patched by Eric Wong.  [ruby-core:41209][Bug #5661]