Couldn't load a self-made "so" file in asterisk

I used c to write a “so” file which needs to invoke another “so” file written by C++ and compiled sololy (it was not compile in asterisk’s makefile ) .
the former file was compile in asterisk 's Makefile and was successfully loaded as it totally and strictly conformed to the flow of asterisk ,the later was wrote by cplusplus and was sololy compiled out of asterisk’s Makefile .when running asterisk , the c++ “so” file failed to be loaded ,asterisk log file gave the hint of “libmp4dll.so” didn’t register itself during load .

the problem has been solved . thx