Calling Ada from C (linux/gnat 4.3.2)

[awdorrin <awdorrin@gmail.com>]

I am trying to port a program originally written on VxWork to Linux.
The main program is written in C and spawns new threads and in the new
threads calls are made to Ada procedures.

In the original program, written with GreenHills AdaMulti, it appears
that there was a call being made that I am assuming was initializing
the Ada Runtime's task stack/control block (rts_init_task()) - however
this is just a guess.

In the version of the program I am migrating, I was seeing things that
made me believe that the Ada thread's did not have their stacks setup
properly, so I added the -fstack-check flag to the build.

Now, the C program creates the new thread, which calls the ada
procedure - and the moment the thread has an opportunity to run - the
application exits with 'raised STORAGE_ERROR : stack overflow
detected'

I cannot get gdb to provide me a backtrace, since the program exits.
If I try to break on the ada procedure name, I get a break, but trying
to 'step' or 'next' keeps me in the main thread until a 'sleep' call
lets the other thread run - at which point it raises the exception.

I am assuming that the ada runtime is initializing and the
STORAGE_ERROR is raised before it gets to execute any of the code in
my Ada procedure.

I have been trying to search to find what the proper way would be to
call an Ada procedure from a C pthread, but have had zero luck. I also
have been unable to determine what the equivalent of the
'rts_init_task' would be with Gnat.

Any have any ideas?