RE: [RFC] Handle GPC specific name for main function

["Pierre Muller" <muller at ics dot u-strasbg dot fr>]

> -----Original Message-----
> From: Joel Brobecker [mailto:brobecker@adacore.com]
> Sent: Wednesday, September 26, 2007 7:58 PM
> To: Pierre Muller
> Cc: gdb-patches@sourceware.org; gpc@gnu.de
> Subject: Re: [RFC] Handle GPC specific name for main function
> 
> Hello Pierre,
> 
> > 2007-09-26  Pierre Muller  <muller@ics.u-strasbg.fr>
> > 	* p-lang.h (pascal_main_name): New function.
> > 	p-lang.c (GPC_MAIN_PROGRAM_NAME_1,
> > 	GPC_MAIN_PROGRAM_NAME_2): New char array constants
> > 	corresponding to the two minimal symbols used
> > 	by GPC compiler.
> > 	(pascal_main_name): Try to find minimal symbol
> > 	corresponding to the entry of GPC compiled programs.
> > 	symtab.c (find_main_name): Try to find
> > 	pascal specific main name by calling pascal_main_name.
> 
> This is mostly OK, except for the tiny comment formatting pointed out
> by Eli. I have a few suggestions:
> 
> > +/* The name of the symbol used by GPC compiler.  */
> 
> I find this is too vague. I suggest something like:
> 
>   /* The name of the symbol that GPC uses as the name of the main
>      subprogram.  There are several possibilities depending on
>      the version of GPC.  */
> 
> I might even go one step further and put a comment for each entry.
> Something like:
> 
>   /* The name of the symbol that GPC uses as the name of the main
>      subprogram (since version ...).  */

  Here, I really need feedback from GPC developers!
 
> And then, for the other one say:
> 
>   /* Older versions of GPC (version ... and older) were using
>      a different name for the main subprogram.  */
> 
> > +static const char GPC_MAIN_PROGRAM_NAME_1[]
> > +  = "pascal_main_program";
> > +static const char GPC_MAIN_PROGRAM_NAME_2[]
> > +  = "_p__M0_main_program";
> 
> Also, I think you might want to order them the opposite way.
> The net effect is that you'll end up trying the newer symbol
> first, and then fallback to the older symbol. When people
> start using the newer compiler, GDB will need to do only one
> symbol lookup to find a match.

  You are perfectly right, chances are higher that
the program will be compiled by a recent or future
GPC.

> > +  /* For GPC, main procedure s a special name.
> > +     .  */
> 
> I think making the comment above a bit more expressive makes
> this comment superfluous.
> 
> > @@ -40,6 +40,7 @@
> >  #include "filenames.h"         /* for FILENAME_CMP */
> >  #include "objc-lang.h"
> >  #include "ada-lang.h"
> > +#include "p-lang.h"
> >
> >  #include "hashtab.h"
> >
> 
> You also need to update Makefile.in, since you added a dependency.

  Funny, while trying to add this, I noticed that
${ada_lang_h} was twice in the dependency list, so
I just replaced the second one with ${p_lang_h}
 
> With these adjustments in, your patch is pre-approved (but please
> remember to give it a round of testing, just in cases).

  Thanks, but my problem is that I am unable to run the testsuite,
and anyhow gdb.pascal is not yet in CVS,
and its mainly there where I expect a change.
 
Pierre