Cannot create dll via make directly in MinGW

[suxpert]

I've searching from the Internet for hours only to find that MinGW need a special treatment when compiling a dll file. That is, ld need a special parameter when creating dll file, if without it, we'll get this message instead of a dll file when linking:

libtool: link: warning: undefined symbols not allowed in i686-pc-mingw32 shared libraries

To solve this problem, we need to pass the -no-defined argument to ld, this can be done via modifying the Makefile.am in src folder, or someone suggest to use the following command instead of a simple make:
make LDFLAGS=-no-undefined