gprof

[Dirk Habighorst]

what does the following error message mean and why do I get it:
gprof: gmon.out file is missing call-graph data 

I am compiling with gcc 2.95.2 with the following options:
gcc -g -pg -o foo foo.c

running the programm './foo' produces the 'gmon.out' file(binary).
running 'gprof foo' results in the error message mentioned above.

I am using Debian Linux with a Kernel 2.2.16

Thanks for your help! 
Dirk
--
  Dirk Habighorst                       e-mail:dirk@epigenomics.de
  Epigenomics AG                        Tel.: +49-30-24345-0
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  10178 Berlin