Issue #9579 has been reported by Eric Wong.

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Feature #9579: [PATCH] ext/extmk.rb: parallelize configure
https://bugs.ruby-lang.org/issues/9579

* Author: Eric Wong
* Status: Open
* Priority: Normal
* Assignee: Eric Wong
* Category: build
* Target version: current: 2.2.0
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This reduces "touch ext/extmk.rb && make -j" time from
roughly 38 to 16 seconds on my 8 core machine with
an otherwise fully-built source tree.

http://bogomips.org/ruby.git/patch?id=bc6acbaa40

git pull git://80x24.org/ruby.git extmk-parallel




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