Thought I'd post an update. I spent last weekend building the support
libraries for MinGW-w64. I also took the opportunity to automate the
build process from start to finish.
I had to do this inside VirtualBox which not only adds significantly to
compiling, the latest version(4.0.4) kept locking up. I see they just
released 4.0.6, but 4.0 works so I'm going to stick with that for now.
I've been attempting to duplicate the TDM64 build process but met with
issues in gtype-desc.c. The errors appear to be undefined types due to
lto support.
I've disabled lto(rebuilding now). If it works I'll integrate GDC into
the process and see about adding lto in later.