[PATCH] libdw: Fix overflow warning on 32bit systems with GCC8 in dwarf_getsrclines.

[Mark Wielaard]

On Wed, May 30, 2018 at 03:54:52PM +0200, Mark Wielaard wrote:
> ndirs is read from the debug data and should be size checked before use.
> 
> https://sourceware.org/bugzilla/show_bug.cgi?id=23248

Pushed to master.