Can 'gprof' show profile info on lib routines such as 'malloc'?

[Congcong]

When I use gprof to profile a program, it seems never show me the profile info on c lib routines such as malloc. But sometimes, profile info on such c lib routines are also important.
I use 'gcc -g -pg' to compile the c source. Should I use other options in order for gprof to show 'malloc'?

Any more suggestions on program profiling?

Thanks!

[Congcong]

Can anybody give a little hint? Or this question is just too boring?

Thanks in advance!