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

[mike stump <mrs@windriver.com>]

> Date: Tue, 4 Dec 2001 16:08:45 -0500
> From: Daniel Jacobowitz <drow@mvista.com>
> To: Neil Booth <neil@daikokuya.demon.co.uk>

> For the curious, this is the exact same problem as c/4053.

> > This happens to me very frequently; I have no idea what causes it.  I
> > have a sneaking suspicion that this GCC bug is what the original post
> > was about, though I'm not sure.

> 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.

Ok, since you did all the hard work, test out the below, and let us
know if it works.  Could someone else run a dejagnu run on it, then we
can submit it for inclusion.

2001-12-04  Mike Stump  <mrs@wrs.com>

	* c-decl.c (c_expand_body): Use the name of the file associated
	with the fndecl, not the current input filename.

*** c-decl.c.~1~	Tue Dec  4 16:52:33 2001
--- c-decl.c	Tue Dec  4 16:54:14 2001
*************** c_expand_body (fndecl, nested_p, can_def
*** 6889,6895 ****
  
    /* Initialize the RTL code for the function.  */
    current_function_decl = fndecl;
!   init_function_start (fndecl, input_filename, DECL_SOURCE_LINE (fndecl));
  
    /* This function is being processed in whole-function mode.  */
    cfun->x_whole_function_mode_p = 1;
--- 6889,6897 ----
  
    /* Initialize the RTL code for the function.  */
    current_function_decl = fndecl;
!   init_function_start (fndecl,
! 		       DECL_SOURCE_FILE (fndecl),
! 		       DECL_SOURCE_LINE (fndecl));
  
    /* This function is being processed in whole-function mode.  */
    cfun->x_whole_function_mode_p = 1;
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