Setting up a MinGW-w64 build environment

http://ascend4.org/Setting_up_a_MinGW-w64_build_environment

First steps

MSYS

Switchable 32- and 64-bit modes

MinGW-w64

SWIG

• Download a pre-compiled 'swigwin' copy of SWIG We used swingwin-x.x.xx.zip.
• Create a folder c:\mingw\msys\opt using Windows Explorer, then copy the 'swigwin-2.0.10' folder out of the Zip archive and into the new location c:\mingw\msys\opt\swigwin-2.0.10
• In MSYS, type gedit ~/.profile, then add the SWIG directory to your PATH in your profile, by adding the following line at the bottom of that file:

export PATH=$PATH:/opt/swigwin-2.0.10

• Close your MSYS window and reopen it, so that the ~/.profile will be re-read.
• Test that SWIG is accessible by typing swig -version. You should see the version number and some other information output.

As SWIG is a code pre-processor, it doesn't matter whether it's 32-bit or 64-bit, they will be perfectly equivalent. That is the reason that we install SWIG under msys rather than in mingw\32 or mingw\64. Note that SWIG version 2.0.5 was known to cause problems with MinGW-w64.