[Development] QtSDK size difference between mingw and msvc version

[Axel Waggershauser]

Hi,

sorry if this is a boring/stupid/old question (I have not found any
related discussion): Why is the installed mingw version of the (5.0.1)
SDK more than 3 times the size (>3.5GB) of the msvc version?

It obviously boils down to the question why especially the debug dlls
are so much bigger (like Qt5Guid.dll: 131MB vs 5MB).

Somewhat related is the question: why is is necessary to have all
those (huge) dlls both in the bin and lib directory? Not having them
duplicated would cut down the above number by about 1.4 GB.

 - Axel