where should be i586-mingw32msvc-pkg-config?-Collection of common programming errors

when i configure libav in ubuntu, there’s an warning like this

WARNING: i586-mingw32msvc-pkg-config not found, library detection may fail.

here’s my configure code.

./configure –target-os=mingw32 –cross-prefix=i586-mingw32msvc- –arch=x86 –prefix=/usr/local/win32 –enable-memalign-hack –disable-gpl –disable-avisynth –disable-postproc –enable-runtime-cpudetect –disable-encoders –disable-muxers –disable-network –disable-devices –enable-shared