[PATCH] gas: accept custom ".linefile <n> ."

[Jan Beulich]

On 14.11.2022 14:43, Nick Clifton wrote:
>> While .linefile is generally intended for gas internal use only, its use
>> in a source file would better not result in an internal error.
> 
> Agreed.
> 
>> Give use
>> of it outside of any macro(-like) construct the meaning of restoring the
>> original (physical) input file name.
> 
> We should document this behaviour in the as.texi file then, so that it
> is "official"...

Do you really think we should? .linefile as a whole is undocumented. If
people use it, then at their own risk (if we made things "official",
later we couldn't later behavior anymore). The point of the change here
was merely to avoid an internal error that I had noticed. The particular
behavior chosen was simply the one easiest to implement (and at least
halfway sensible) while addressing the issue.

I am, btw, doing further work in this area, which includes zapping
.linefile from listings (where I think it should never have appeared,
but I didn't think of that aspect several months ago). Such zapping
would imo also be unreasonable if the directive became "official".

Jan