'main' enters in gcc-4.1

[Perret Yannick]

Hello,

I'm using '-finstrument-functions' for a while
to make function-level profiling.
Recently, I compiled gcc-4.1 (without problem)
and used it for the same purpose.

Here is the result :
  Enter main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=0
  Enter main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=1
  Enter main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=0
  Exit main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=6
  Exit main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=1
  Enter main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=176
  Enter main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=0
  Exit main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=1
  Exit main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=1
  Enter orig (essai.c:23) [0x8048f20] from 0x8049448 - PID=1774 - elaps=1
(...)
  Exit main (essai.c:41) [0x80490b0] from 0x4003be36 - PID=1774 - elaps=198

This test program is a very small C program with 'main' calling two 
functions
in a loop, compiled with -O2. These messages are generated by my
__cyg_profile_{enter|exit} functions.

as you can see GCC generates 3 consecutive calls to 'main', then 2 
exits, 2 enters,
and 2 exits.
At last it is coherent, but the behavior does not appear in older 
versions of GCC.

Can you explain me why I see that behavior ? Is it "good" or is it a bug ?
Of cours this is a little disturbing for people that make the assumption 
that
'main' is called once :o)

Thanks in advance.

Regards,
--
Yannick Perret