Hi,

When I compile the attached program

  (with compilers available directly from Debian's repositories)

I can observe a (non-deterministic) deadlock.

When I remove

	%!

from the printf function inside the SIGALRM's handler, the deadlock never seem to occur.

Obviously, interference can be easily introduced in concurrent programs; I was just surprised that even something like

	%!

can cause it.

Isn't this something, that could be avoided in this case?