Hello, I am new to the list and I am not sure it's the good place for such question. If I am at the wrong place, please give me hints on where I should ask this question. First, I would like to understand the content of libgcc_s.so ? My second question is When does a program require libgcc_s ? I am asking those question because I am having trouble to generate a static version of my program using gcc 3.3.X on slackware. The same build process executed on GCC 4.0.0 on redhat works well. I have checked for the availability of the libgcc_s.so in both case and find this library at the same place in both case. The annoying error message follows /bin/sh ../../../../../libtool --tag=CXX --mode=link g++ -g -O2 -o yml_worker_xtremweb -all-static -L/home/ode/these/dev/build/lib -lutil -lpthread yml_worker_xtremweb-YmlWorker.o ../../../../../src/Yml/Worker/libymlworker.la g++ -g -O2 -o yml_worker_xtremweb -static yml_worker_xtremweb-YmlWorker.o -L/home/ode/these/dev/build/lib ../../../../../src/Yml/Worker/.libs/libymlworker.a /home/ode/these/dev/build/lib/libutil.a -L/usr/lib -L/usr/i486-slackware-linux/bin -L/usr/i486-slackware-linux/lib -L/usr/lib/gcc-lib/i486-slackware-linux/../../../i486-slackware-linux/lib -L/usr/lib/gcc-lib/i486-slackware-linux/../.. -ldl /usr/lib/libexpat.a -lpthread /usr/lib/./libstdc++.a -lm -lc -lgcc_s /usr/lib/gcc-lib/i486-slackware-linux/3.3.6/../../../../i486-slackware-linux/bin/ld: cannot find -lgcc_s collect2: ld returned 1 exit status The problem here is that libgcc_s.so is avvailable in /usr/lib which appears in the -L line I also made this simple check ld -L/usr/lib -lgcc_s and ld complains on the _start symbol missing which means ld find the lib. Thanks for your help