Actions
Bug #17349
closedRake での並行実行における正規表現マッチングの異常
Status:
Closed
Assignee:
-
Target version:
-
ruby -v:
ruby 2.7.2p137 (2020-10-01 revision 5445e04352) [x86_64-linux]
Description
小さな再現コードが作成できなかったのですが、以下のように Rake で並行実行すると正規表現のマッチングがおかしくなることがあるように見えます。
再現手順¶
$ git clone https://github.com/mruby/mruby
$ cd mruby
$ git checkout 0cb3a718
$ rake -m CONFIG=boxing clean gensym
Cleaned up target build folder
GEN build/boxing-no-m64-i32/presym
GEN build/boxing-no-m64-i32/include/mruby/presym.inc
GEN build/boxing-no-m32-i32/presym
GEN build/boxing-no-m32-i64/presym
(snip)
rake aborted!
NoMethodError: undefined method `*' for nil:NilClass
/mruby/tasks/presym.rake:81:in `block (4 levels) in <top (required)>'
/mruby/tasks/presym.rake:80:in `map'
/mruby/tasks/presym.rake:80:in `block (3 levels) in <top (required)>'
/mruby/tasks/presym.rake:69:in `map'
/mruby/tasks/presym.rake:69:in `block (2 levels) in <top (required)>'
Tasks: TOP => gensym => /mruby/build/boxing-no-m64-i64/presym
(See full trace by running task with --trace)
rake aborted!
エラーが発生しているのは以下の部分です。
prefix
や suffix
の値がおかしくなっているために、macro_to_symbol[[prefix, suffix]]
が nil
なり例外になっています。本来であればこの値は nil
にならないはずのものです。
補足¶
-
rake
に-m
を付けないで並行実行にしなければ発生しません。 - こちらの環境では少なくとも30回に1回くらいは上記のエラーが発生します。
- 正規表現のマッチ結果は上記とは違う異常になることもあるようです。
Files
Updated by jeremyevans0 (Jeremy Evans) over 3 years ago
- Related to Bug #17507: Regexp capture groups ignored sometimes in some multithreaded environments (possible race condition) added
Updated by jeremyevans0 (Jeremy Evans) about 3 years ago
I reviewed the mruby presym.rake
file and was able to come up with a self contained reproducible example, which I have attached. I confirmed the issue is still present in Ruby 3.0 (this error shows the issue happened between 600 and 1200 iterations):
$ ruby cfiles.rb
......#<Thread:0x00000747b72298f8 cfiles.rb:16 run> terminated with exception (report_on_exception is true):
cfiles.rb:59:in `block (3 levels) in <main>': undefined method `*' for nil:NilClass (NoMethodError)
from cfiles.rb:58:in `map'
from cfiles.rb:58:in `block (2 levels) in <main>'
from cfiles.rb:47:in `map'
from cfiles.rb:47:in `block in <main>'
from cfiles.rb:20:in `block (2 levels) in a'
^Ccfiles.rb:26:in `join': Interrupt
from cfiles.rb:26:in `map'
from cfiles.rb:26:in `a'
from cfiles.rb:64:in `<main>'
I also confirmed that https://github.com/ruby/ruby/pull/4734, which fixes #17507, also fixes this issue. With that pull request, the attached example program runs all 60,000 iterations without error.
Updated by jeremyevans0 (Jeremy Evans) over 2 years ago
- Status changed from Open to Closed
Actions
Like0
Like0Like0Like0