[RFC] .fill does not accept forward labels

[Jan Beulich]

>>> On 06.10.17 at 13:25, <krebbel@linux.vnet.ibm.com> wrote:
> Hi,
> 
> running gas on: (x86-64)
> 
> .global _start
> .text
> .fill (2f-1f), 1, 0x90
> 1:
>         nop
> 2:
> 
> produces:
> 
> t.s: Assembler messages:
> t.s:3: Warning: symbol ".L21" undefined; zero assumed
> 
> ... while it works fine with backward references. Other pseudo commands like 
> .skip work for both.
> 
> A quick hack fixes this for me without causing testsuite regressions on 
> x86-64. However, the current
> code looks intentional to me. Does anybody know what the reason is for 
> erroring out if the symbol
> isn't known yet?

If the label changes position during later processing (e.g. relaxation),
your fill range would end up being wrong.

Jan