I have recently noticed that - when compiling with icc (and ifc) - nm doesn't always neccesarily recognise the file format of resultant libraries. Specifically, we have an MPI package (MPICH 1.2.4-derived) that builds to several libraries, none of which nm is able to report on.
The distro is RH7.3 running on dual Xeons.
Confusing. Anybody else seen this?