I checked the plugins folder It seems they have been built
for example this folder :C:\Qt\vsStatic\qtbase\plugins\imageformats contains these files
Qt Code: 
  1. qico.lib
  2. qico.prl
  3. qicod.prl
  4.  
  5. qmng.lib
  6. qmng.prl
  7. qmngd.prl
  8.  
  9. qsvg.lib
  10. qsvg.prl
  11. qsvgd.prl
  12.  
  13. qtga.lib
  14. qtga.prl
  15. qtgad.pel
  16.  
  17. qtiff.lib
  18. qtiff.prl
  19. qtiffd.prl
  20.  
  21. qwbmp.lib
  22. qwbmp.prl
  23. qwbmpd.prl
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What should I put in .pro file now ?(I didn't find anything useful in other sites ! can you provide me an example?)