Re: [c/4053] Re: problems debugging gcc

[Neil Booth <neil at daikokuya dot demon dot co dot uk>]

Daniel Jacobowitz wrote:-

> Well, it isn't in the debug format code; the file information in the
> RTL is wrong.  And there's nothing obviously incorrect about the code
> in cb_file_change...
> 
> Aha, I think I see it.  cb_file_change updates input_filename as it
> reads.  Compile the testcase from the PR with a breakpoint on
> cb_file_change and a breakpoint on emit_line_note.  If I had to guess,
> I'd say that the problem was input_filename describing the state of the
> lexer where it used to describe the state of the parser.  In
> c_expand_body is the line:
>   init_function_start (fndecl, input_filename, DECL_SOURCE_LINE (fndecl));
> 
> DECL_SOURCE_LINE is fine.  input_filename isn't.

Cool!  This looks like it.  I'll take a closer look and post a patch
if it works.

Thanks a lot for the detective work!

Neil.