[RFA] Stabs: Ignore N_BNSYM/N_ENSYM entry types

[RFA] Stabs: Ignore N_BNSYM/N_ENSYM entry types

Trying to debug gdb with itself,
I stumbled on the following complaints
Unknown symbol type 0x2e
or
Unknown symbol type 0x4e

It appears that those corrspond to N_BNSYM and N_ENSYM,
which are MacOS extensions of stabs debugging format.
But these extensions have been used inside gcc probalby
for a while already, see:
https://gcc.gnu.org/ml/gcc/2004-08/msg00157.html

As the only purpose of these entries is to allow for removal
of stabs information if the function is removed,
it can be safely ignored by GDB.

This patch simply adds those two entry types to the list
of ignored entry type in read_dbx_symtab function.

Is this OK?

Pierre Muller

2014-10-03  Pierre Muller  <muller@sourceware.org>

	* dbxread.c (read_dbx_symtab): Also ignore N_BNSYM/N_ENSYM.