next assertion found (ldo.c:679: lua_resume: L->nCcalls == ((from) ? from->nCcalls : 0))

[nobody <nobody+lua-list@...>]

My "fuzzer" (for lack of a better word) has become too clever for its
own good and started setting per-line debug hooks that error(),
producing too many spurious "crashes".  So I locked it away in a
coroutine... and it immediately crashed.  Oh well. :-)

A lucky random seed got me
.....coroutine.resume(table.unpack(debug.getregistry())).....,
which translates into:


-- begin test case --
A = coroutine.running( )
B = coroutine.create( function( )  coroutine.resume( A )  end )
coroutine.resume( B )
-- end test case --

Wrapping print() around the resumes, you get (with lua_assert #defined):
  false    cannot resume non-suspended coroutine
  lua.debug: ldo.c:679: lua_resume: Assertion
    `L->nCcalls == ((from) ? from->nCcalls : 0)' failed.
  Aborted(134)
i.e. the resume of A fails with the expected error message, but the
resume of B runs into the assertion while returning.

(Previous problems in that corner: [1] (and maybe more))


Notably (& furthermore), coroutine.wrap will not hit the assertion,
instead the main thread (A) is claimed to be both dead _and_ alive:

-- begin test case #2 --
local co = coroutine
A = co.running( )
co.wrap( function( )
  print( co.resume( A ) )  --> false, "cannot resume dead coroutine"
  print( co.status( A ) )  --> "normal"
end )( )
-- end test case #2 --


-- Marco

[1]: http://lua-users.org/lists/lua-l/2013-10/msg00745.html