On Mon, 2015-05-04 at 13:19 -0600, Jeff Law wrote:
> On 05/01/2015 06:56 PM, David Malcolm wrote:
> > As a relative newcomer to GCC, one of the issues I had was
> > becoming comfortable with the linemap API and its internal
> > representation.
> >
> > To familiarize myself with it, I wrote a dumping routine
> > to try to visualize how the source_location space is carved
> > up between line maps, and what each number can mean.
> >
> > It struck me that this would benefit others, so this patch
> > adds this visualization, via an undocumented option
> > -fdump-locations, and adds a text file to libcpp's sources
> > documenting a simple example of compiling a small C file,
> > with a header and macro expansions (built using the
> > -fdump-locations option and a little hand-editing).
> >
> > gcc/ChangeLog:
> > 	* common.opt (fdump-locations): New option.
> > 	* input.c: Include diagnostic-core.h.
> > 	(get_end_location): New function.
> > 	(write_digit): New function.
> > 	(write_digit_row): New function.
> > 	(dump_location_range): New function.
> > 	(dump_labelled_location_range): New function.
> > 	(dump_location_info): New function.
> > 	* input.h (dump_location_info): New prototype.
> > 	* toplev.c (compile_file): Handle flag_dump_locations.
> >
> > libcpp/ChangeLog:
> > 	* include/line-map.h (source_location): Add a reference to
> > 	location-example.txt to the descriptive comment.
> > 	* location-example.txt: New file.
> Maybe "dump-internal-locations"?  Not sure I want to bikeshed on the 
> name any more than that.   If you feel strongly about the option name, 
> then I won't stress about it.
> 
> 
> 
> > +void
> > +dump_location_info (FILE *stream)
> > +{
> > +  if (0)
> > +    line_table_dump (stream,
> > +		     line_table,
> > +		     LINEMAPS_ORDINARY_USED (line_table),
> > +		     LINEMAPS_MACRO_USED (line_table));
> Should the if (0) code go away?
> 
> > +
> > +  /* A brute-force visualization: emit a warning at every location.  */
> > +  if (0)
> > +    for (source_location loc = 0; loc < line_table->highest_location; loc++)
> > +      warning_at (loc, 0, "this is location %i", loc);
> > +      /* Alternatively, we could use inform (), though this
> > +	 also shows lots of locations in stdc-predef.h */
> And again.
> 
> 
> So I think with removing the if (0) code and the possible option name 
> change this is good to go.

Thanks.  I removed the if (0) code and renamed it to
-fdump-internal-locations.

Bootstrapped&regrtested on x86_64-unknown-linux-gnu (Fedora 20).

Committed to trunk as r223163 (attached).