merge [86460] from trunk, fix bootstrap on mingw

[SVN r86516]
Merge 84402 from ^/trunk

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  r84402 | jhunold | 2013-05-21 14:23:20 +0200 (Di, 21 Mai 2013) | 4 lines
  
  Fix: cache file loading and saving must use native paths
  
  Fixes caching at least on Windows platform
  
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[SVN r86519]