Failed to load library

I ported GoAhead to nios under uclinux.

But it gived out Failed to load shared library 12, some other program gived out Fail to load library 1.

what does that mean?

Does it has matter to do with the selection between uclibc and uclib-c in menuconfig of kernel?

Or should I select some libraris in menuconfig such as flex and libPCAP?(I don't know what can they do, just for example)

thx