Fix types of size, num_symbols in fancy_backtrace. Close #779
Fix types of size, num_symbols in fancy_backtrace. Close #779

What it doesn't fix, though is the fact that libiberty isn't shipped
by homebrew's binutils anymore, cf:
https://github.com/Homebrew/homebrew/pull/20760
and https://gcc.gnu.org/onlinedocs/libiberty/Using.html#Using

Apparently we should be shipping our own sources, but seeing our
delicate build process, it seems unrealistic for now.

davidhesselbom/rock,fredrikbryntesson/rock,davidhesselbom/rock,zhaihj/rock,magic-lang/rock,thomasfanell/rock,ooc-lang/rock,magic-lang/rock,shamanas/rock,fredrikbryntesson/rock,ooc-lang/rock,kirbyfan64/rock,cogneco/rock,shamanas/rock,zhaihj/rock,marcusnaslund/rock,ds84182/rock,fasterthanlime/rock,thomasfanell/rock,cogneco/rock,jonathanudd/rock,jonathanudd/rock,marcusnaslund/rock,fasterthanlime/rock,kirbyfan64/rock,ds84182/rock