Issue #6904 has been reported by shyouhei (Shyouhei Urabe).

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Bug #6904: make -j all fails (sometimes)
https://bugs.ruby-lang.org/issues/6904

Author: shyouhei (Shyouhei Urabe)
Status: Assigned
Priority: Low
Assignee: nobu (Nobuyoshi Nakada)
Category: build
Target version: 2.0.0
ruby -v: bbb6b5e84e53b17c5c08072cae05aed6de6e3abe


make -jは現在まともに動いていません。

http://travis-ci.org/#!/ruby/ruby/jobs/2194633
> cp: cp: cp: cannot create regular file `../../.ext/common/openssl'cannot create regular file `../../.ext/common/openssl': File exists: File existscannot create regular file `../../.ext/common/openssl': File existscp: 

想像ですがGNU Makeが再帰的に動く場合の-jの挙動が理解されていないのではないかと思います(gmakeではサブディレクトリも並列で動く)。


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