RFA/RFC: Add stack recursion limit to libiberty's demangler [v3]

[Nick Clifton]

Hi Richard,

>>   * The description of the DMGL_RECURSE_LIMIT option in demangle.h has
>>     been enhanced to add a note that if the option is not used, then
>>     bug reports about stack overflows in the demangler will be rejected.
> 
> Shouldn't we make it fool-proof by instead introducing a DMGL_NO_RECURSION_LIMIT
> flag and when not set default to limiting recursion?

Well I wanted the patch to be backwards compatible. Just on the
general principle of not surprising users/programmers by changing 
things without telling them first.

I could change this of course, but I would rather have Ian's blessing
first.

Cheers
  Nick