gprof does not display memset - callgrind does

[Chris Stankevitz]

Hello,

Why are calls to memset not appearing in my gprof output?

My c++ app was compiled and linked with -p -pg.  gprof does not display 
calls to memset (but does show functions I wrote).  The same exe does 
display calls to memset when it is run within callgrind.  Below I 
present how I envoke gprof and callgrind.

./bin/gcc/profile/prog
gprof ./bin/gcc/profile/prog -l

valgrind --tool=callgrind ./bin/gcc/profile/prog

Thank you for your help,

Chris