[PPL-devel] Strange behavior of `pl -dump-runtime-variables' on SWI-Prolog 5.4.7

[Roberto Bagnara]

On a system where SWI-Prolog 5.4.7 has been configured
with a simple `configure', this gives

$ /usr/local/bin/pl -dump-runtime-variables
CC="gcc";
PLBASE="/usr/local/lib/pl-5.4.7";
PLARCH="i686-linux";
PLLIBS="-ldl -lreadline -lncurses -lm -lrt ";
PLLIB="-lpl";
PLLDFLAGS="-export-dynamic  -O3 -pthread";
PLSOEXT="so";
PLVERSION="50407";
PLSHARED="yes";
PLTHREADS="yes";

Instead, on a system where SWI-Prolog 5.4.7 has been
configured with `./configure --disable-mt',
the same command gives

$ /tmp/junk/bin/pl -dump-runtime-variables
CC="gcc";
PLBASE="/tmp/junk/lib/pl-5.4.7";
PLARCH="i686-linux";
PLLIBS="-ldl -lreadline -lncurses -lm ";
PLLIB="";
PLLDFLAGS="-export-dynamic  -O3";
PLSOEXT="so";
PLVERSION="50407";
PLSHARED="yes";
PLTHREADS="no";

For some reason, PLLIB is now assigned the empty string.
This makes `plld' fail miserably and, since I don't see
any connection between multithreading and the observed
behavior, I wonder if this is a bug.
All the best,

      Roberto

-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it