PCC (http://pcc.ludd.ltu.se) released pcc-1.1.0 very recently.
(pcc-1.0.0 was released in October, 2014 after a decade of silence).
So I decided to give it a try.
I was not able to use PCC to bootstrap ATS2. There were simply
too many issues to address.
I succeeded in using PCC to compile the C code generated from the
ATS2 source of a few simple examples in ${PATSHOME}/doc/EXAMPLE/INTRO.
The way PCC handles linking is problematic on my system. So I used PCC to
generate .o files and then used GCC to link the .o files into an excutable.