On Fri, Oct 18, 2019 at 07:51:38AM -0500, Segher Boessenkool wrote:
[ ... ]
> Using reserved names (like those starting with two underscores) is UB
> already.
What does "UB" mean?
> > > To get this conforming, the linker would need to export a symbol to the start
> > > of the section and the length of the section, IMHO.
> >
> > Right, but we do not have that today. 8-(
>
> We have had it since over 25 years:
>
> Thu Aug 18 15:37:45 1994 Ian Lance Taylor (ian@xxxxxxxxxxxxxxxxxxx)
>
> Make the ELF linker handle orphaned sections reasonably. Also,
> define __start_SECNAME and __stop_SECNAME around sections whose
> names can be represented in C, for the benefit of symbol sets in
> glibc.
???
I was talking about exporting start+length instead of start+stop.
Having start+length would allow a confirming implementation, because pointer
arithmetic on unrelated objects would no longer be needed:
unsigned long *dst = &_s_bss;
for (n = 0; n < _l_bss / sizeof (unsigned long); n++)
dst[n] = 0;
--
Josef Wolf
jw@xxxxxxxxxxxxx
