Description of problem:

If I'm a debugger, and I call:
ptrace(PTRACE_SETOPTIONS, kid, 0, PTRACE_O_TRACEEXIT)
for a child process I'm debugging, and if that child
process is multi-threaded, then when the process
calls _exit(0) instead of the SIGTRAP with the PTRACE_EVENT_EXIT
code in the exit status that I expect, I get a 0x7f status
that means "stopped with signal 0"


Version-Release number of selected component (if applicable):

This is in the i686 2.6.21-1.3228.fc7 kernel on my fedora 7
box (dual xeon system).

How reproducible:

every time I run the test program (which I'll attach).

Steps to Reproduce:
1. gcc -o exitcode exitcode.c -lpthread && ./exitcode
  
Actual results:

gcc -o exitcode -g exitcode.c -lpthread && ./exitcode
waitpid status: 0x7f
FAIL: unexpected stop signal 0

Expected results:

gcc -o exitcode -g exitcode.c -lpthread && ./exitcode
waitpid status: 0x6057f
PASS: got SIGTRAP with event code PTRACE_EVENT_EXIT

Additional info:

I tried the test program on both rhel4 and rhel5 systems and it
got expected results (but they were uniprocessors, so if it has
something to do with thread timing that might not be an interesting
result).