Hi, I have problems linking the an MPI program with an external shared library in MPICH3.1 on Vesta BGQ. The error message I get is: mpicc -g -Wall -fPIC -Wextra -I. -c hello.c -o hello.o mpicc -g -Wall -fPIC -Wextra -I. -c dyn_lib.c -o dyn_lib.o mpicc -shared -Wl,-soname,libdyn_lib.so -o libdyn_lib.so dyn_lib.o mpicc -g -Wall -fPIC -Wextra -I. -o hello hello.o -dynamic -Wl,-rpath, -L. -ldyn_lib /bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/lib/gcc/powerpc64-bgq-linux/4.4.7/../../../../powerpc64-bgq-linux/bin/ld: hello: hidden symbol `__dso_handle' in /bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/lib/gcc/powerpc64-bgq-linux/4.4.7/crtbegin.o is referenced by DSO /bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/lib/gcc/powerpc64-bgq-linux/4.4.7/../../../../powerpc64-bgq-linux/bin/ld: final link failed: Bad value collect2: ld returned 1 exit status make: *** [hello] Error 1 The problem seems to be caused by a __dso_handle symbol in the MPICH library (both in static and dynamic libraries), but I do not know what the solution is: [fisaila@vestalac2 lib]$ nm libmpich.so | grep __dso_handle U __dso_handle My MPICH3.1 is configured with: ./configure --prefix=/home/fisaila/software/mpich-3.1-THR_MULT-nodebug-install2rpath --host=powerpc64-bgq-linux --with-device=pamid --with-file-system=bg+bglockless --enable-thread-cs=per-object --with-atomic-primitives --enable-handle-allocation=tls --enable-refcount=lock-free --disable-predefined-refcount CC=powerpc64-bgq-linux-gcc Any suggestion is welcome Thanks Florin