[ptp-dev] debugger update

[Greg Watson <g.watson@xxxxxxxxxxxx>]

Beth, Clement,

I've made some changes to the sdm that I hope will fix the problem  
you saw when hitting a breakpoint on a set of processes. It should  
also make debugging MPI programs more reliable. Please test.

Clement, there is a problem with the UI losing track of processes.  
Here's how to repeat:

1. Compile test program:

#include <stdio.h>
#include <stdlib.h>

int
main(int argc, char *argv[])
{
	printf("starting...\n");
	printf("continue process 0, leave process 1 suspended\n");
	
	for (;;)
		/* infinite */;
		
	printf("never reached\n");
	exit(0);
}

2. Start debugger with 2 processes.

3. With both processes suspended in main(), continue process 0 using  
the control in the Debug (not Parallel Debug) view. Leave process 1  
suspended.

4. Suspend both processes using control in Parallel Debug view.

5. Step both processes using control in Parallel Debug view. Notice  
that process 0 starts running (ok), but process 1 does not step  
(bad). Suspend processes again.

6. Try continuing both processes. Only process 0 starts running.  
Suspend processes again.

7. Try terminating both processes. Only process 0 terminates.

After step 4, it looks like any commands from the Parallel Debug view  
are only being sent to process 0.

Greg