Re: Program_Error from library level task declaration...

["Theodore E. Dennison" <dennison@escmail.orl.mmc.com>]

Dale Stanbrough wrote:
> I've tried to create a library level semaphore to be used
> for screen locking. The semaphore is the standard implementation
> using a task (yes, I know a protected object would be better).
> 
> The declaration is...
> 
> with semaphores; use semaphores;
> package screen_lock is
> 
>         screen:semaphore;
> 
> end screen_lock;
> 
...

> However this causes a program_error. I'm at a bit of a loss as
> to how to fix this. Does anyone have any bright ideas?

It would help to see the code for "semaphores" as well. Typically,
I see program error when,

   o  Someone tries to rendezvous with a task that has terminated.
   o  The code depends on the order of package elaboration (and the
      compiler guesses wrong).
   o  A function reaches the "end" without executing a "return" 
      statement.

(Note that if the "semaphore" task contains a terminate alternative,
the task may terminate once your main task terminates.)
-- 
T.E.D.          
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