hush crashing on a Blackfin architecture

[Pavel]

Hi!
  I'm trying to update BB on a blackfin based system (small PBX board
derived from IP-01 by Rowetel) and I can't get hush running. 
  There is bb 1.16.1 on the board. When I recompile exactly the same, it
works. However current stable (1.31.1) always ends up with ILL or SEGV or
sometimes BUS when trying to invoke hush, either in the interactive mode
or by a script (having #!/usr/bin/busybox hush on its first line).
  I did a regressin check and I found that the latest BB version which
works is 1.18.5. The crash appears since 1.19.0.
  All the other applets (even interactive ones like vi with all the
possible options turned on) are working.
  I can't strace it, strace doesn't work on the system. There aren't any
other symptoms (for example, dmesg and logs are not affected) so I'm
just clueless where to start. I diff'ed hush.c from 1.18.5 and 1.19.0
but there are too many changes especially with signal handling and other
system interactions that I'm lost in it.
  I'm using bfin-linux-uclibc- platform prefix and the toolchain seems
to be versioned as ADI-2014R1-RC2. Possibly it's too old, but I didn't
get luck with newer ones (the board is even older, from about 2010).
  It's also possible that the system includes contained in the toolchain
(I don't have and can't find any SDK files for the actual system) are slightly
incompatible with installed uclibc, but I successfully compiled a lot of
other system utilities for it and almost all are working, including the
substantial part of BB itself..
  So, any hints would be highly appreciated!
  With regards,
    Pavel