Bug #8492: ObjectSpace.after_gc_start_hook aborts with GC.stress

• Status: Closed
• Assignee: ko1 (Koichi Sasada)
• Target version: 2.1.0
• ruby -v: ruby 2.1.0dev (2013-06-05 trunk 41080) [x86_64-freebsd9.1]
• Backport: 1.9.3: DONTNEED, 2.0.0: DONTNEED

[naruse (Yui NARUSE)]

以下を実行すると assert(during_gc > 0) に失敗して abort します。
ruby -robjspace -e'ObjectSpace.after_gc_start_hook=proc{};GC.stress=true;{}'
gc.c:3818 の
gc_event_hook(objspace, RUBY_INTERNAL_EVENT_GC_START, 0 /* TODO: pass minor/immediate flag? */);
実行後に、during_gc が 0 になっている模様。

[ko1 (Koichi Sasada)]

随分放置してしまってすみません。
これ、今でもなりますか？　手元ではなんか

$ ./ruby -robjspace -e'ObjectSpace.after_gc_start_hook=proc{};GC.stress=true;{}'
セグメンテーション違反です

などと出てしまう。これはこれでまずかろう、という気もしますが...。

[nobu (Nobuyoshi Nakada)]

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

This issue was solved with changeset r43245.
Yui, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

vm_trace.c: fix infinite hook

• thread.c (rb_threadptr_execute_interrupts): flush postponed job only
  once at last.
• vm_trace.c (rb_postponed_job_flush): defer calling postponed jobs
  registered while flushing to get rid of infinite reentrance of
  ObjectSpace.after_gc_start_hook. [ruby-dev:47400] [Bug #8492]

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 1.9.3: UNKNOWN, 2.0.0: UNKNOWN to 1.9.3: DONTNEED, 2.0.0: DONTNEED