I have been beating myself up the last day trying to get this to work. I am using mingw64 to compile my projects, from an arch linux distro. No matter what I do, I cannot get it to properly link freeimage using 64 bit. Things I have tried:
Used the package 'mingw-w64-freeimage' from the AUR
Compiled 64-bit using VC2010
Compiled 64-bit using Code::Blocks (using x86-64 mingw64 gcc)
All of these result in the same thing, undefined references when linking, both statically and dynamically. When I use the 32-bit pre built binaries I can link and compile perfectly (using i686-w64-mingw32-gcc).
I could not build the library from my linux machine because the makefile and readme for mingw seem to be made for MSYS/mingw32 rather than mingw-w64 and I don't want to manually edit everything. The package from the AUR already did all of that and it still did not work.
On the other hand, why are 64bit binaries not available for download? Would have saved me a lot of headache.