Ld.exe cannot find -lusrp on windows

I have successfully installed gnuradio on windows xp but i am having a
slight problem running the C++ files. When i enter the following command
on
MinGW:
$ g++ usrp_test_c++.cpp -o testusrp -lusrp

I get the following error:

C:\MinGW\bin…\lib\gcc\mingw32\3.4.5…\mingw32\bin\ld.exe:
cannot
find -lusrp
collect2: ld returned 1 exit status

Please guide me to figure out the problem. I have the files

libusrp-0.dll
libusrp.dll.a
libusrp.la
libusrp.lai

in the following folder:

C:\gnuradio-3.1.3\usrp\host\lib\legacy.libs

Is there any file missing? or if i need to set the Path variable then
which
one needs to be set?

Regards
Zainab