Re: [PATCH 2/7] Generate virtual locations for tokens

[Jason Merrill <jason at redhat dot com>]

On 08/09/2011 10:54 AM, Dodji Seketeli wrote:
> +      goto ftrack_macro_expansion_with_arg;
> +
> +    case OPT_ftrack_macro_expansion_:
> +    ftrack_macro_expansion_with_arg:

Instead of the goto, just write /* Fall through.  */

> +consumption if necessary. Value @samp{0} of @var{level} de-activates
> +this option just as if no @option{-ftrack-macro-expansion} was present
> +on the command line. Value @samp{1} tracks tokens locations in a
> +degraded mode for the sake of minimal memory overhead. In this mode
> +all tokens resulting from the expansion of an argument of a
> +function-like macro have the same location. Value @samp{2} tracks
> +tokens locations completely. This value is the most memory hungry. It
> +is the default value.

"It is the default value" sounds to me like no -ftrack-macro-expansion 
option is equivalent to -ftrack-macro-expansion=2, rather than =0.

> +     expansion of arguments of function-like macro. all macro
> +     expansion. 2 Means we do track all macro expansions. This last

Seems like the "all macro expansion" is left over from a previous 
version of this sentence.

> +/* This describes some additional data that is added to the macro
> +   token context of type cpp_context, when -ftrack-macro-expansion is
> +   on.  */
> +typedef struct
> +{
> +  /* The node of the macro we are referring to.  */
> +  cpp_hashnode *macro_node;
> +  /* This buffer contains an array of virtual locations.  The virtual
> +     location at index 0 is the virtual location of the token at index
> +     0 in the current instance of cpp_context; similarly for all the
> +     other virtual locations.  */
> +  source_location *virt_locs;
> +  /* This is a pointer to the current virtual location.  This is used
> +     to iterate over the virtual locations while we iterate over the
> +     tokens they belong to.  */
> +  source_location *cur_virt_loc;
> +} macro_context;

Why track virtual locations separately rather than use them directly as 
the src_loc of the tokens?

Jason