Re: [rfa] Extra warning in solib-svr4

[Mark Kettenis <mark dot kettenis at xs4all dot nl>]

> Date: Fri, 30 Mar 2007 10:45:19 -0400
> From: Daniel Jacobowitz <drow@false.org>
> 
> Suppose you take a static linked program, strip it, and run it under
> GDB.  You'll get this warning:
> 
> warning: shared library handler failed to enable breakpoint
> 
> You can reproduce this without stripping - you need to have no .interp
> section and no functions named _start or main, that's all.  So this
> actually came up when using KGDB to debug a Linux kernel.

Trying to debug a stripped static program is a rather silly thing to
do.  That said ...

> The shared library breakpoint is generally not important in this
> case.  It's more important if there was a .interp but something went
> wrong while trying to load the referenced executable; that's got a
> separate warning:
> 
>       warning (_("Unable to find dynamic linker breakpoint function.\n"
>                "GDB will be unable to debug shared library initializers\n"
>                "and track explicitly loaded dynamic code."));
> 
> I think the more general warning is not useful, since it has a high
> correlation with non-shared programs.  OK to remove it?

... I think the simplification is good, so no objection from me.

> 2007-03-30  Daniel Jacobowitz  <dan@codesourcery.com>
> 
> 	* solib-svr4.c (enable_break): Simplify return value.
> 	(svr4_solib_create_inferior_hook): Do not warn if enable_break fails.
> 
> Index: solib-svr4.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/solib-svr4.c,v
> retrieving revision 1.61
> diff -u -p -r1.61 solib-svr4.c
> --- solib-svr4.c	9 Jan 2007 17:58:58 -0000	1.61
> +++ solib-svr4.c	30 Mar 2007 14:39:46 -0000
> @@ -979,8 +979,6 @@ exec_entry_point (struct bfd *abfd, stru
>  static int
>  enable_break (void)
>  {
> -  int success = 0;
> -
>  #ifdef BKPT_AT_SYMBOL
>  
>    struct minimal_symbol *msymbol;
> @@ -1146,13 +1144,9 @@ enable_break (void)
>  	  return 1;
>  	}
>      }
> -
> -  /* Nothing good happened.  */
> -  success = 0;
> -
>  #endif /* BKPT_AT_SYMBOL */
>  
> -  return (success);
> +  return 0;
>  }
>  
>  /*
> @@ -1357,10 +1351,7 @@ svr4_solib_create_inferior_hook (void)
>      }
>  
>    if (!enable_break ())
> -    {
> -      warning (_("shared library handler failed to enable breakpoint"));
> -      return;
> -    }
> +    return;
>  
>  #if defined(_SCO_DS)
>    /* SCO needs the loop below, other systems should be using the
>