[ruby-cvs:59458] nagachika:r52307 (ruby_2_2): merge revision(s) 52124: [Backport #11591]

[nagachika at ruby-lang.org]

nagachika	2015-10-27 23:50:55 +0900 (Tue, 27 Oct 2015)

  New Revision: 52307

  http://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=52307

  Log:
    merge revision(s) 52124: [Backport #11591]
    
    * configure.in: check for libunwind.h, which is not available in
      very old OS X SDK.  [ruby-core:71080] [Bug #11591]

  Modified directories:
    branches/ruby_2_2/
  Modified files:
    branches/ruby_2_2/ChangeLog
    branches/ruby_2_2/configure.in
    branches/ruby_2_2/version.h
    branches/ruby_2_2/vm_dump.c