Issue #8492 has been reported by naruse (Yui NARUSE).

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Bug #8492: ObjectSpace.after_gc_start_hook aborts with GC.stress
https://bugs.ruby-lang.org/issues/8492

Author: naruse (Yui NARUSE)
Status: Assigned
Priority: Normal
Assignee: ko1 (Koichi Sasada)
Category: core
Target version: current: 2.1.0
ruby -v: ruby 2.1.0dev (2013-06-05 trunk 41080) [x86_64-freebsd9.1]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


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。


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