[RFA] bug in symtab.c:lookup_block_symbol()'s search method

[Andrew Cagney]

>> IMNSHO gdb 5.1 can not be released with the symbol binary search
>> lookup broken as it has been for the last year.
> 
> Broken?
> You mean slower.
> It works *correctly*, just not as *efficiently* as it could.
> Big difference.

gdb is measured against many criteria, one is performance.  if gdb's 
performance drops, gdb has regressed.  some would describe it as broken.

in some some situtations - replacing a macro by a function say - such a 
regression is considered acceptable.  in other cases - such as an 
algorithm change that is ment to improve performance - it is not.

andrew