example does not work

[GoogleCodeExporter]

What steps will reproduce the problem?
1. compile the example from the Project Home, link with -lconcurrency
2. run the example
3.

What is the expected output? What do you see instead?

The context should have switched to the writer upon coro_call(cw, r);

What version of the product are you using? On what operating system?

svn r31, Linux x86_64, glibc 2.11.3

Please provide any additional information below.

I don't think the setjmp logic works at all.  longjmp will always stay inside
coro_call() because there's also the setjmp that goes with it.
setjmp doesn't record the stack of the previous frame but the current one; and 
that's coro_call().

Original issue reported on code.google.com by sfreu...@gmail.com on 1 Nov 2013 at 10:46