while compiling my code with -pg option
i got the following error:

ld (prelink):
-pg incompatible with -shared; assuming -nopg

any idea to overcome this problem?
how can i use gprof profiler for a program using shared libraries?

The error message means what it says -- gprof won't work for shared libraries. It's not a bug, gprof's just not meant for it. You'll need to link it statically or use something else.

If you use Linux, you might find sysprof useful. It'd probably do better on shared libraries than executables since shared libraries by definition have symbol information...

One choice -

Don't compile a shared library - create an archive ie., library.a Then you can link against it for profiling.

Note: monitor normally records time in and calls to library members when the library is compiled normally but the "local" code is compiled -pg Yours should do that, so it will show up in a profiler.