problem with dlopen when used from multiple threads

[sjhill at realitydiluted.com]

> When dlopen() is used to dynamically load libraries from different threads,
> program crashes sometimes with segmentation fault. This problem is observed
> with 0.9.27 as well as 0.9.28 libraries on MIPS malta platform. Tool chain
> is based on gcc 3.3.6, binutils 2.14.90.0.8 and kernel is 2.4.31
> 
Most likely this is because we do not have the dynamic loader lock in
uClibc that glibc has. When doing TLS and NPTL I thought about
implementing it, but passed for now as it is a corner case of sorts.
If someone else wants to take a stab at it, great. If not, I can get
to it in a couple of months.

-Steve