thread.c: no allocation during GC
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48911 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
thread.c: no allocation during GC
the exception not to allocate new objects, during GC.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48911 b2dd03c8-39d4-4d8f-98ff-823fe69b080e