The dynsym section is parsed by objdump/grep.  It's terrible and
needs to be implemented in C++ to reduce dependence on external tools
knowing what they are doing.

In this case, the terrible pattern matching with grep caused a symbol
defined in the binary to be missed, because `grep -v UND` was used
to determine whether a symbol "mattered".  1) symbol names might have
UND and get eliminated accidentally, but 2) (what really happened)
was that the symbol was defined in a section without a "link" field
in the dynsym section, thus objdump displayed the section name as UND
and thus the code skipped the symbol.  Don't use objdump to parse ELF
files!