Exceptions and thread safety

[Anjul Srivastava]

I am told that 
exception handling in gcc is not thread safe. I am not sure what this precisely 
means, but I would imagine that if you have two threads and both enter exception 
handling code, then something nasty will happen.
 
1.    
Could somebody more knowledgeable please characterise this problem (if it 
exists) more precisely.
2.    
I would like to work on a solution to this problem. Since this would be my first 
foray into gcc, I would really appreciate any mentoring as to how to go about 
fixing the problem. (I have a reasonable knowledge of compiler design & 
techniques, C/C++ programming, and Unix threads).
 
Anjul.