mingw is used to build QEMU from source on Windows.
Go to MinGW download page, download mingw-get-inst-20101030.exe, and run the installer.
Use pre-packaged repository cataloguse 20101030
select "C Compiler", "MSYS Basic System" and "MinGW Developer ToolKit"
After installing minGW successfully, open an msys terminal by clicking c:/mingw/msys/1.0/msys.bat (suppose minGW is installed in c:/mingw. The same to below when "c:/mingw" is used)
run below commands to install more packages needed:
mingw-get.exe install libpthread mingw-get.exe install libexpat
create file link for libpthread.a
cd /mingw/lib ln -s libpthread.dll.a libpthread.a (windows may create hard file instead of symbolic link. It is fine as well)
Download source package of libSDL-1.2 from here. Copy SDL-1.2.14.tar.gz into c:/mingw/msys/1.0/home/xxx/.
tar xzvf SDL-1.2.14.tar.gz cd SDL-1.2.14 ./configure --prefix=/mingw make make install
Download source package of zlib-1.2.3 from here. Get zlib-1.2.3 source directory and copy it into c:/mingw/msys/1.0/home/XXX/
cd zlib-1.2.3 ./configure --prefix=/mingw make make install
Download source package of libpng 1.4.5 from here. Copy libpng-1.4.5.tar.gz into c:/mingw/msys/1.0/home/xxx/.
tar xzvf libpng-1.4.5.tar.gz cd libpng-1.4.5 ./configure --prefix=/mingw make make install