[uClibc]signal handler = segmentation fault

[Daniel M. DiPasquo]

We're attempting to track a problem where, upon retun from a signal
handler, the process dies with a SIGSEGV.  We've replicated  the problem
with a simple program that runs correctly when linked with glibc.
Investigation so far shows that glibc uses the rt_sigaction() system call
while uClibc uses sigaction() system call.

Additional information: an strace reveals that when the sigaction()
system call happens, the sa_flags slot of the sigaction struct contains a
number of set flags (notably, the SA_STACK flag) and some "garbage" value,
even though we explicetly set sa_flags to 0 before the sigaction call.