> -rdynamic isn't going to help libunwind, it's for glibc's built-in backtrace library which you simply shouldn't use. -rdynamic exports global symbols from th

> -rdynamic isn't going to help libunwind, it's for glibc's built-in backtrace library which you simply shouldn't use. -rdynamic exports global symbols from the main binary so that they're available to satisfy dependencies of dynamically linked libraries and modules. For example, a Perl or Lua interpreter, or an Apache daemon, will use -rdynamic so that its symbols can satisfy the dependencies of binary modules, rather than requiring the engine implementation to be linked via a shared library itself, which is more brittle. It's sort of midway between static and dynamic linking in terms of ensuring everybody is using the same implementation of a shared framework.