Runtime crashes inside glib main loop

[Jaume Delclòs Coll]

Running scheme code from a foreign-lambda called using a glib callback can make the runtime crash. The bug is not easy to reproduce, since every small change to the code can make it easier or harder to trigger.

I have been able to trigger it only when doing a significant amount of work on the callback, but taking more time to return doesn't necessarily make it easier to trigger, and sometimes multiple calls are needed.

The output when crashing is this:

test: runtime.c:2797: C_save_and_reclaim: Assertion `av > C_temporary_stack_bottom

av < C_temporary_stack_limit' failed.

I'm running this on the following release (installed from the Arch Linux repos):

Version 4.11.0 (rev ce980c4)
linux-unix-gnu-x86-64 [ 64bit manyargs dload ptables ]
compiled 2016-05-28 on yves.more-magic.net (Linux)

I'll attach my test code, which depends on bind (egg) and glib.

[Jaume Delclòs Coll]

Test code

[Jaume Delclòs Coll]

Ran it on valgrind to see if anything weird popped up