> Yes, but it's not the writes or reads that segfaults, it's 
> malloc() itself!

I'll go repeating what everyone else has been saying:

Faults do not necessarily occur at the same place in the code as the
bug.  Sometimes a bug on one line of one module will not fault, but
merely place an obstacle where another module will trip.  

> The shell works perfectly on FreeBSD/x86 where it was developed, the
> problem is only on the Alpha!

Alphas are DIFFERENT.  

All the world is not an x86, and the x86 is far more forgiving of any
number of sins of portability (e.g., alignment) than the alpha.  Data
structures are different sizes because pointers are twice as large on
alpha.

Does the code pass gcc -Wall -Werror cleanly?  Does it pass lint(1)?

Do you cast between char * and other pointer types ever?

Do you cast between pointer types and integer types?

					- Bill