Issue #11201 has been updated by Usaku NAKAMURA.

Backport changed from 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN to 2.0.0: WONTFIX, 2.1: REQUIRED, 2.2: REQUIRED

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Bug #11201: pkg_config NoMethodError when finding other -config program
https://bugs.ruby-lang.org/issues/11201#change-53196

* Author: Hans Mackowiak
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-05-28 trunk 50658) [x86_64-linux]
* Backport: 2.0.0: WONTFIX, 2.1: REQUIRED, 2.2: REQUIRED
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where it does work (existing package)

~~~ruby
pkg_config("gtk+-x11-2.0") #  => ["-pthread", "", "-lgtk-x11-2.0 -lgdk-x11-2.0 -lpangocairo-1.0 -latk-1.0 -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lpangoft2-1.0 -lpango-1.0 -lgobject-2.0 -lglib-2.0 -lfontconfig -lfreetype"] 
pkg_config("gtk+-x11-2.0", "version") # => "0.28" 
~~~

where it does work (non-existing package)

~~~ruby
pkg_config("wx-bla", "version") # => nil 
pkg_config("wx-bla") #  => nil 
~~~

where it maybe not work (other (pkg)-config program)

~~~ruby
pkg_config("wx", "version") # => "3.1.0" 

pkg_config("wx") #either should try to return the same stuff as pkg_config("gtk+-x11-2.0") if possible, or if not return nil
~~~
~~~
NoMethodError: undefined method `scan' for nil:NilClass
	from /usr/local/rvm/rubies/ruby-head/lib/ruby/2.3.0/shellwords.rb:73:in `shellsplit'
	from /usr/local/rvm/rubies/ruby-head/lib/ruby/2.3.0/mkmf.rb:1819:in `pkg_config'
	from (irb):11
	from /usr/local/rvm/rubies/ruby-head/bin/irb:11:in `<main>'
~~~



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