What's the difference between the MinGW project and the 32-bit portion of the MinGW-w64 project? Does the 32-bit portion of MinGW-w64 have any relation to x64 at all?
It seems like their compilers do the exact same things...
One looks like it "cross compiles", from 64 bit to 32 bit, whereas the other looks native.
That was just a quick look though, so I could be a long long way off the mark here......
EDIT: This is only somewhat true. A better explanation is provided here
The MinGW from http://www.mingw.org/ does only support gcc 32 bit (host and target). The independent minGW-w64 project provides support for 64 bit, and also supports a much larger part of the Windows API. The MinGW-w64 project provide official binary builds: These can be grabbed either from the personal build directories of the developers (the most popular being rubenvb), or from associated but independent projects like mingw-builds or tdm-gcc.
Source: http://wiki.qt.io/MinGW-64-bit
As said by others MinGW-w64 is a fork of the original MinGW which supports both 32 and 64bit x86 processors. You can find the original motivation for the fork here:
https://sourceforge.net/p/mingw-w64/wiki2/History/
Regarding the differences you can find a list here:
There's a bit of insight into this in the Wikipedia talk page on the MinGW article. Basically, it appears that the MinGW-w64 project is a fork of the MinGW source base. I have found very little clear information on the details of why the fork happened (although this mailing-list post and this rebuttalimplies it was some form of the usual sort of open-source politics), or of the subsequent differences between the two projects.
To a first approximation, they're the same; the differences will come in in subsequent development.
来源：https://stackoverflow.com/questions/5619341/mingw-w32-vs-mingw