I am a developer of the GEOPM software https://geopm.github.io. Like many profiling tools we require use of the PMPI interface to interpose on MPI calls. To support this we use the LD_DYNAMIC_WEAK environment variable as is documented in ld.so(8) http://man7.org/linux/man-pages/man8/ld.so.8.html. Doing so causes a hang when loading libucs.so.0.0.0. This issue is documented in detail in the bug on our github page here:
Attached to that issue is a tar file that contains a minimal reproducer and the output on our system. Any help in resolving why enabling weak symbols in shared libraries causes a hang in loading libucs.so.0.0.0 would be appreciated.