Re: swsusp.S: meaningfull assembly labels

[Patrick Mochel]

> > drow@nevyn:~% cat a.s
> > BUF = 0x1
> > code:
> >         mov %eax, 0
> > drow@nevyn:~% as -o a.o a.s
> > drow@nevyn:~% as -o b.o a.s
> > drow@nevyn:~% ld -o a a.o b.o
> > ld: warning: cannot find entry symbol _start; defaulting to 0000000008048074
> > drow@nevyn:~% nm a.o
> > 00000001 a BUF
> > 00000000 t code
> > drow@nevyn:~% nm a
> > 00000001 a BUF
> > 00000001 a BUF
> > 08049084 A __bss_start
> > 08049084 A _edata
> > 08049084 A _end
> > 08048074 t code
> > 0804807c t code
> >
> > LD won't even warn about duplicate absolute symbols unless they have
> > different values.
> >
>
> But they ARE different values. They will probably always be different
> values, and they end up with the same name, that `ld` sees and complains.

No, it doesn't complain, that's the point. According to nm(1):

       For each symbol, nm shows:

          The symbol value, in the  radix  selected  by  options
           (see below), or hexadecimal by default.

          The  symbol  type.   At  least the following types are
           used; others are, as well,  depending  on  the  object
           file  format.   If  lowercase, the symbol is local; if
           uppercase, the symbol is global (external).

Symbols in a source file that are static are tagged with a 't' as well.
Read System.map for more proof of this.

The patch is fine, especially since I think it's based on something I've
posted in the past. :) The one thing I'd always done differently, though,
was to prefix the labels with '.', since I thought that was what kept it
local. But, after I RTFM'd, I find that's not even necessary.


	Pat
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