Re: gas new (2.20) rebuffer_line() excessive read() syscalls

[nick clifton]

Hi Jim,

> I've got a C language source code TU that is 1.3 MiB large. I didn't
> write it (I know better), but I have to make it coexist in a rather
> lengthy system build, and the leader of the system build team is
> justifably upset with me.


> As we see, the compilation time grows by a factor of 15X. I see the
> rebuffer_line() (listing.c:541) routine

Since this function is only used by the listing code, you could just not 
enable listing when assembling your huge application...


> It looks like most of listing.c was rewritten for 2.20. I tried removing
> the fseek(FILE *, 0, SEEK_SET) call and made a couple of refactoring
> changes to make sure I'm seeking  the proper source line.

Unfortunately your patch does not work.  It removes the fseek and 
rereading of the source file, but it does not actually search backwards 
to find an earlier line, which is the entire point of the 
rebuffer_line() function.

Instead, please could you try out the attached patch and let me know if 
it works for you.

Cheers
  Nick

listing.c.patch
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