Re: gas bug: out-of-order .file directives do not work

[Alan Modra]

On Wed, Feb 22, 2006 at 02:22:40PM -0500, address@hidden wrote:
> This happens on x86-linux in gas 2.14 and 2.16, and the bug
> is still in the source code in the latest CVS version.
> 
> .file directives do not work unless they are emitted in numerical
> order. For example, this fails:
> 
>       .file   2       "/something_else"
>       .loc    2 402 1
>       .file   1       "/something"
>       .loc    2 402 1
> 
> $ as bar.s
> bar.s: Assembler messages:
> bar.s:4: Error: unassigned file number 2
> 
> 
> It looks like a 'get_filenum' bug. 'get_filenum' tries to correctly
> handle file numbers being declared out of order, e.g. it understands
> there may be "holes" in the numbering space containing NULL
> filenames. But it always sets files_in_use to one beyond the latest
> number it has seen, effectively forgetting about any higher-numbered
> file that was already declared.
> 
> Fortunately, the patch is trivial.
> 
> 
> --- dwarf2dbg.c.orig  2006-01-11 11:16:47.000000000 -0500
> +++ dwarf2dbg.c       2006-02-22 13:38:53.000000000 -0500
> @@ -415,19 +415,20 @@
>        files_allocated = i + 32;
>        files = (struct file_entry *)
>       xrealloc (files, (i + 32) * sizeof (struct file_entry));
>  
>        memset (files + old, 0, (i + 32 - old) * sizeof (struct file_entry));
>      }
>  
>    files[i].filename = num ? file : xstrdup (file);
>    files[i].dir = dir;
> -  files_in_use = i + 1;
> +  if (i + 1 > files_in_use)
> +    files_in_use = i + 1;
>    last_used = i;
>    last_used_dir_len = dir_len;
>  
>    return i;
>  }
>  
>  /* Handle two forms of .file directive:
>     - Pass .file "source.c" to s_app_file
>     - Handle .file 1 "source.c" by adding an entry to the DWARF-2 file table

Thanks.  I've applied this to mainline sources.

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre