[RFC] slipping in symbol prefixes automagically via PROVIDE() in linker scripts

[Nick Clifton]

Hi Mike,

> with the new binutils-2.17, it'd be good to switch to using the generic elf.sc 
> file ... but this _ prefix is standing in the way 

Which symbols in the elf.sc need this prefix and do not already have it 
?  I looked through the file and it seems that most symbols are provided 
in an underscore prefixed version and a non-underscore prefixed version. 
  Or is it that you want to have *double* underscore prefixed versions 
and single underscore prefixed versions ?  (If so, are the double 
underscore prefixed versions really necessary ?)

... there seems to be two
> ways to deal with this at the moment:
> - copy elf.sc to bfin.sc again and just insert the _ symbols as needed
> - tweak PROVIDE() to automatically insert a configurable prefix

The cleanest way would be to edit elf.sc so that PROVIDEd symbols had an 
optional prefix.  eg change:

   ${RELOCATING+${END_SYMBOLS-_end = .; PROVIDE (end = .);}}

to

   ${RELOCATING+${END_SYMBOLS-_end = .; PROVIDE (${PREFIX}end = .);}}

and in your bfin.sh file define PREFIX as "_".

> from what i can tell after reading the ld docs, PROVIDE is generally for 
> setting up automatic symbol values when referenced via higher level code 
> (like C) ... so making PROVIDE "smarter" and having it insert the same 
> prefixes that higher level language parsers seems like a good idea to me :)

Changing PROVIDE would be a bad idea in my opinion.  It would prevent 
linker scripts from being able to define symbols outside of the 
namespaces of higher level languages, and this might be needed.  (eg for 
example for defining symbols used by ROM monitors to handle program 
start up).

Cheers
   Nick